Impact of a clinical pharmacist on optimising the quality use of medicines according to the acute coronary syndrome (ACS) secondary prevention guidelines and medication adherence following discharge in patients with ACS in Sri Lanka: a prospective non-randomised controlled trial study protocol

OBJECTIVES

Ensuring quality use of medicines (QUM) through clinical pharmacy services can improve therapeutic outcomes of patients diagnosed with acute coronary syndrome (ACS). The major objective of this study is to demonstrate the added value of a clinical pharmacist to the medical and nursing team providing care to patients with ACS on the continuation of quality use of the patients' medicine after discharge.

STUDY DESIGN

This protocol outlines a prospective, non-blinded, non-randomised, controlled interventional study.

STUDY SETTING

The study will be conducted at the professorial medical wards of a tertiary care teaching hospital in Sri Lanka.

PARTICIPANTS

Sample size will be 746 patients in both control and intervention arms. Patients diagnosed with ACS who are 18 years old or above and expected to visit the hospital for their routine clinic follow-ups after discharge will be recruited and randomised 1:1 to either the intervention group or the control group. Patients who are diagnosed and suffering from psychological disorders will be excluded from this study.

INTERVENTIONS

The planned interventions that will be delivered at discharge include review and optimisation of medications, assessing patient adherence and providing discharge medication counselling. Data will be collected at recruitment, 1 month, 3 months and 6 months' time intervals in both groups. Improvement of patients' medication adherence, reduction of hospital readmissions, reduction of drug-related problems, the attitude of doctors and nurses towards clinical pharmacy services and the cost-effectiveness of the clinical pharmacy services will be the major outcomes of this study.

ETHICS AND DISSEMINATION

Ethical approval for this study has been obtained from the ethics review committee, Faculty of Medicine, University of Peradeniya (2019/EC/26) and the trial is registered at the Sri Lanka Clinical Trials Registry. The results of this study will be disseminated via conference proceedings, journal publications and thesis presentations.

TRIAL REGISTRATION NUMBER

SLCTR/2019/039.

Relationship Between Alcohol Co-Ingestion and Clinical Outcome in Pesticide Self-Poisoning: A Systematic Review and Meta-Analysis

AIM

Alcohol is a commonly co-ingested compound during self-poisoning with pesticides. Clinical experiences suggest alcohol co-ingestion (or withdrawal) makes patient management more difficult after self-poisoning and may contribute to poor clinical outcomes. We aimed to systematically review the world literature to explore the relationship between alcohol co-ingestion and outcome in pesticide self-poisoning.

METHODS

We searched 13 electronic databases and Google scholar, conducted citation searching and a review of reference lists to find studies which investigated the relationship of alcohol with clinical outcome of pesticide self-poisoning in different countries. Thirteen studies, including 11 case series/reports and two cohort studies were considered for inclusion.

RESULTS

Meta-analysis showed that alcohol co-ingestion in pesticide self-poisoning was associated with increased risk of death [odds ratio (OR) 4.9, 95% confidence interval (CI) 2.9-8.2 P<0.0001] and that alcohol co-ingested group required intubation eight times more often than non-co-ingested group in organophosphorus insecticide self-poisoning (OR 8.0, 95% CI 4.9-13.0 P<0.0001). Cases who co-ingested alcohol were older than non-alcohol group in two studies. One cohort study demonstrated that alcohol co-ingestion was associated with larger pesticide ingestions but did not itself affect the outcome.

CONCLUSIONS

This systematic review indicates that alcohol co-ingestion may worsen clinical outcome in pesticide self-poisoning.

Dose ingested, vomiting, and outcome in patients ingesting a standard paraquat 20SL formulation

BACKGROUND

FAO specifications for liquid paraquat dichloride SL formulations require the use of an emetic agent to stimulate vomiting within 30 min of ingestion. To date, there is no high-quality evidence of efficacy, despite use of the PP796 emetic since 1979. We first examined the validity of patients' self-reported dose of paraquat ingested by examining the relationship with blood paraquat concentration and time to death for patients ingesting the standard paraquat SL formulation in a Sri Lankan cohort. As a secondary outcome, we assessed whether ingestion resulted in vomiting within 30 min and whether vomiting was associated with good outcome.

METHODS

Patients presenting with paraquat SL self-poisoning were prospectively studied in ten Sri Lankan hospitals in 2003-08. Data on reported dose ingested, incidence and timing of vomiting after ingestion, treatment received, plasma paraquat concentration, and outcome were collected prospectively on presentation to hospital. Time between ingestion and blood sampling was incorporated by covariate adjustment.

RESULTS

441 patients were recruited to the case series, presenting a median (IQR) of 3.0 (1.5-8.1] h post ingestion. Outcome was known for 435 patients of whom 322 (74.0%) died within 42 days, a median of 1.3 (0.6-4.4) days post ingestion. Median reported dose ingested was 15 to <30 mL. There was a highly significant linear trend between log plasma paraquat and reported dose ingested (p < .001); adjustment for the log of the time from ingestion to sampling further improved the model fit. Case fatality and median time to death also showed good agreement with estimated ingestion amount. 347/438 patients (79.2%) were stated to have vomited before reaching the study hospital with 300 (68.5%) vomiting within 30 min of ingestion; time to vomiting was unknown for a further 12 (2.7%). The proportion vomiting was strongly associated with reported dose ingested (p < .001); of note the proportion vomiting within 30 min only increased to 83.3% for the highest ingestion group. Patients vomiting within 30 min had higher plasma paraquat concentrations (p = .008), and higher hazard ratio in the adjusted Cox regression model of 2.01 (95% CI 1.45-2.77) compared to those who did not. Vomiting within 30 min was associated with a higher case fatality (241/295 [81.7%] vs 68/125 [54.4%], p < .001). Forty-three (47.3%) of the 91 patients who did not vomit before reaching hospital died (one had unknown outcome).

CONCLUSION

Importantly, we found good agreement between reported dose ingested and plasma paraquat concentration, case fatality, and time to death, suggesting that the reported dose is a valid marker for the dose ingested. Vomiting occurred within 30 min for 68.5% of patients, exceeding the characteristics for a purported effective emetic in the FAO specifications. However, vomiting within 30 min was associated with approximately double the risk of death compared to those who did not vomit, larger paraquat ingestions, and higher blood paraquat concentrations. In addition, death occurred in many patients who did not vomit, and the proportion vomiting within 30 min only reached 82.1% for the highest ingested dose group. Overall, we found no evidence of benefit resulting from incorporation of the emetic, suggesting that the current FAO specification is not effective at preventing deaths after ingestion of the paraquat SL formulation.

Pre-vaccination RT-PCR negative contacts in workplace settings show high, SARS COV-2 neutralizing antibody levels

Background

Asymptomatic SARS-CoV-2 infection occurring in RT-PCR negative individuals represent a poorly characterized cohort with important infection control connotations. While household and community-based studies have evaluated seroprevalence of antibody and transmission dynamics in this group, workplace-based data is currently unavailable.

Methods

A cohort study was carried out in July 2021, during and immediately following the peak of the 3^rd wave of COVID-19 in Sri Lanka, prior to mass vaccination. A total of 92 unvaccinated individuals between the ages of 17–65 years were purposively sampled from an office and two factory settings. The selected cohort that had been exposed to RT-PCR positive cases in the workplace was tested RT-PCR negative. Serological samples collected six weeks post exposure were tested for anti-SARS-CoV-2 neutralizing antibody.

Results

The seroprevalence for SARS-CoV-2 specific neutralizing antibodies in the overall cohort was 63.04% (58/92). Seroprevalences in the office setting, factory setting 1 and factory setting 2 were 69.2% (9/13), 55.7% (34/61) and 83.33% (15/18), respectively. Primary risk factor associated with seropositivity was face to face contact with no mask for > 15 min (p < 0.024, Odds Ratio (OR); 5.58, 95%CI;1.292– 25.65). Individuals with workspace exposure had significantly higher levels of neutralizing antibodies than those who did not (percentage neutralization in assay 63.3% (SD:21)vs 45.7% (SD:20), p = 0.0042), as did individuals who engaged socially without protective measures (62.4 (SD:21.6)% vs 49.7 (SD:21)%, p = 0.026).

Conclusion

There was a high seroprevalence for SARS-CoV-2 specific neutralizing antibodies among RT-PCR negative contacts in workplace settings in Sri Lanka. Higher levels of transmission of SARS-CoV-2 infection than estimated based on RT-PCR positive contact data indicate need for targeted infection control measures in these settings during future outbreaks.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-14381-5.

Acute fungicide self-poisoning - a prospective case series

BACKGROUND

Pesticide self-poisoning is a global clinical and public health problem. While self-poisoning with insecticides and herbicides has been extensively studied, there is minimal literature on acute fungicide self-poisoning. We aimed to study the clinical course and outcome of fungicide self-poisoned patients recruited to a prospective cohort in Sri Lanka.

METHODS

We conducted a prospective study of patients presenting with fungicide self-poisoning to nine hospitals in Sri Lanka between 2002 and 2020. Patients were enrolled by clinical research assistants, with clinical outcomes being recorded at regular review for each patient.

RESULTS

We identified 337 cases of self-poisoning with fungicides (alcohol as only co-ingestant), including 28 different fungicides across 5 different fungicide classes. Median time from ingestion to examination was 3.1 (1.8-5.7) h. Nearly all presented to hospital fully conscious (GCS 15, 15-15)- only 27 patients (8.0%) presented with reduced GCS (<15) and only 2 (0.6%) had GCS 3/15. Most patients (333/337, 98.8%) made a full recovery, of whom only eight (2.37%) required intubation and ventilation. Four patients died (case fatality rate: 1.2%; 95% CI 0.0-23.4) after ingestion of edifenphos (n = 2), propamocarb and pyraclostrobin.

CONCLUSION

Fungicide self-poisoning appears to be less hazardous than insecticide or herbicide self-poisoning, with a substantially lower case fatality in the same cohort. Edifenphos is an exception to this 'less toxic' rule; as a WHO Class Ib highly hazardous pesticide, we recommend its withdrawal from, and replacement in, global agricultural practice. Propamocarb should be listed in the WHO hazard classification as propamocarb hydrochloride to reflect the higher toxicity of the common agricultural formulation. Pyraclostrobin currently has no WHO classification; one is urgently required now that its ingestion has now been linked the death of a patient. Additional prospective clinical data on fungicide self-poisoning is required to expand knowledge on the effects of these diverse compounds.

Osmolal and anion gaps after acute self-poisoning with agricultural formulations of the organophosphorus insecticides profenofos and diazinon: A pilot study

Self-poisoning with organophosphorus (OP) insecticides is an important means of global self-harm. The insecticides are formulated with solvents that may also contribute to toxicity. We set up a study to detect changes in osmolal and anion gaps following ingestion of OP insecticides. We recruited consecutive patients admitted to a Teaching Hospital, Sri Lanka, with a history of OP self-poisoning. The osmolal and anion gaps were calculated on admission and at 4, 24 and 72 h post-ingestion together with ethanol concentration. Forty-nine patients were recruited (28 profenofos, 10 diazinon, one coumaphos, one chlorpyrifos, one phenthoate and eight unknown OP). Only modest increases in osmolal and anion gaps were noted. Small rises in osmolal gap above the upper limit of normal were noted in 16/49 (32.7%) of all cases, 9/28 (32.1%) profenofos cases and 4/10 (40.0%) diazinon cases. The anion gap was raised in 24/49 (49.0%) of all cases, 15/28 (53.6%) profenofos cases and 5/10 (50.0%) diazinon cases. We observed a trend for a fall in osmolal gap during the first 24 h, followed by an increase up to 72 h. There was no correlation between the anion gap and serum lactate concentration, indicating that a lactic acidosis was not responsible for the anion gap. Formate, which could have explained the increased gap, was not detected in any of the samples; ketoacids (beta-hydroxybutyrate and acetoacetate) were not measured. This pilot study found that profenofos and diazinon poisoning caused only modest increases in the osmolal and anion gaps in a minority of cases.

The efficacy of physiotherapy interventions in the treatment of adhesive capsulitis: A systematic review

BACKGROUND

Adhesive capsulitis is a debilitating condition which causes the capsule of the gleno-humeral joint to thicken and contract progressively. The effectiveness of various non-operative methods has been demonstrated to improve the pain, range of motion (ROM) and functional status of patients with adhesive capsulitis.

OBJECTIVE

This study aims to review recent evidence on the efficacy of physiotherapy interventions in the treatment of adhesive capsulitis.

METHODS

PubMed, Physiotherapy Evidence Database (PEDro), Science Direct and Cochrane databases were searched for studies published since 2013. The search terms included: Frozen shoulder, adhesive capsulitis, physical therapy, rehabilitation, manual therapy, mobilization, exercise, education, and electrotherapy. The search was limited to studies published in English and studies that used human subjects.

RESULTS

Quality scores of 33 articles were reviewed according to the Sackett's critical appraisal criteria and the grades of recommendation were determined for physiotherapy interventions used in the studies.

CONCLUSION

The empirical evidence suggests that certain physical therapy techniques and modalities are strongly recommended for pain relief, improvement of ROM, and functional status in patients with adhesive capsulitis, while others are either moderately or mildly recommended. However, the efficacy of one treatment modality over another is uncertain. The poor methodological rigors demonstrated in most of the reviewed studies emphasize the urgent need of properly conducted, adequately sampled randomized controlled trials with adequate follow up to determine the superior combination of treatment.

Acute phenthoate self-poisoning: a prospective case series

BACKGROUND

The clinical characteristics following self-poisoning with organophosphorus (OP) insecticides differs according to the insecticide ingested. Phenthoate is a dimethoxy WHO Hazard Class II OP pesticide with limited literature on its clinical characteristics and outcome. We aimed to better understand its clinical characteristics by studying patients with phenthoate self-poisoning in Sri Lanka.

METHODS

We conducted a prospective cohort study of patients presenting with phenthoate self-poisoning to eight hospitals in Sri Lanka between 2002 and 2018. Clinical outcomes were recorded for each patient. Blood samples for measuring plasma phenthoate concentration, cholinesterase activity, and response to oximes were available for a very small number of patients recruited to a clinical trial.

RESULTS

Two hundred and ninety-two patients who ingested agricultural phenthoate formulations were included in the study. Median time to admission was 3.9 (IQR 2.4 - 6.8) h. Forty-two (14.4%) patients were intubated, mostly (30/37, 81%) within 24 h of ingestion (median time to intubation 7.2 [IQR 2.6-20.9] h). Median duration of intubation was 74.8 (IQR 26.8-232.5) h; the longest duration in a survivor was 592 h. Nineteen died (case fatality 6.5%, 95% CI 4.0-10.0); median time to death was 37 (IQR 16 - 101.7) h. Median plasma phenthoate concentration in patients with samples (n = 81) was 135 (IQR 62.7-356.5) ng/mL (0.42 µmol/mL [0.2 to 1.1 µmol/mL]). Five of six patients receiving pralidoxime chloride 2 g showed an initial increase in AChE and BuChE activity that was not sustained despite an infusion of pralidoxime.

CONCLUSION

Phenthoate self-poisoning has a 6.5% case fatality rate. Most patients who experience respiratory failure undergo early intubation; most deaths occurred among those patients who were intubated less than 24 h after ingestion. There was a non-sustained increase in cholinesterase activity with pralidoxime, but further studies are required to analyse the extent to which oximes are clinically effective in phenthoate self-poisoning.

Development of a Treatment Protocol for Cobra (Naja naja) Bite Envenoming in Dogs

There is limited information on clinical profiles, treatment, and management aspects of Indian cobra (Naja naja) bite envenoming in dogs in Sri Lanka. Dogs with cobra bites presented to the Veterinary Teaching Hospital (VTH), University of Peradeniya, were prospectively studied over a period of 72 months; local and systemic clinical manifestations and hematological abnormalities were recorded. We studied 116 cobra bite envenomings in dogs. A grading system was established using a combination of anatomical site of fang marks, as well as local and systemic clinical manifestations. Accordingly, treatment strategies were established using Indian polyvalent antivenom (AVS). Pain and swelling at the bite site were major clinical signs observed, while neurotoxic manifestations (mydriasis, wheezing, and crackles) were detected in most dogs. Leukocytosis was observed in 78% of them. Statistical analysis revealed that the grading scores obtained were compatible to initiate AVS administration according to the severity. The minimum number required was 2 AVS vials (range 2-12). Almost 20% of the dogs developed wheezing, crackles, hypersalivation, restlessness, and dyspnea as adverse reactions to AVS treatment. Necrotic wounds on bitten anatomical sites developed in 19% of the dogs and 2.5% developed acute kidney injuries as a consequence of envenoming crisis. Despite treatment, 3% of dogs died. No dry bites were recorded.

Thrombotic microangiopathy and acute kidney injury following Sri Lankan Daboia russelii and Hypnale species envenoming

Context: Thrombotic microangiopathy (TMA) resulting in acute kidney injury (AKI) is an important complication of venomous snakebites. We aimed to describe TMA secondary to Russell's viper (Daboia russelli) and hump-nosed viper (Hypnale spp.) bites and assess the effect of different treatments.Materials and methods: We undertook a prospective observational study of patients with AKI secondary to snakebite over a two-year period. Data recorded included: demographic details, clinical and laboratory features, treatment, complications and outcomes, until hospital discharge and at three months post-discharge. TMA was defined as the development of microangiopathic hemolytic anemia and thrombocytopenia along with AKI. Treatment with therapeutic plasma exchange (TPE; also known as plasmapheresis) and/or fresh frozen plasma (FFP) was determined by the treating clinician. Antivenom was given to all patients with evidence of systemic envenoming following Russell's viper bites.Results: Fifty-nine patients were included in the analysis. Thirty-three (56%) were males and median age was 56 years. Forty-five (76%) developed TMA while a further 11 and two developed isolated thrombocytopenia and microangiopathic hemolytic anemia, respectively. Presence of TMA was associated with increased dialysis requirements (5 vs. 3) and longer hospital stay (18 vs. 12 days). Of the patients with TMA, nine received TPE with or without FFP infusions. The use of TPE was not associated with improved outcomes in patients with TMA based on requirement for blood transfusion, recovery of thrombocytopenia, requirement of dialysis and duration of hospital stay. Patients who did not receive TPE had better renal function at three months compared to patients who received this treatment.Conclusion: Presence of TMA in patients with Daboia and Hypnale bites was associated with a more prolonged course of AKI. Patients with TMA who were treated with TPE did not have improved early or late outcomes compared to patients who were not treated with TPE.

The clinical toxicity of imidacloprid self-poisoning following the introduction of newer formulations

BACKGROUND

Self-poisoning with imidacloprid has been previously shown to have low toxicity in humans. Since 2007 newer formulations of Imidacloprid with unknown solvents have been introduced and the potential clinical consequences of these products have not been described.

METHODS

Clinical and demographic data were prospectively collected from admissions following oral ingestion of imidacloprid from seven hospitals in Sri Lanka. Data was collected from 2002 to 2007 in an already published study. We compared this data on poisonings collected from 2010 to 2016 following the introduction of new formulations of imidacloprid.

RESULTS

From 2002-2007, there were 56 patients with ingestion to imidacloprid compared to 67 patients post 2010 The median time to presentation prior to 2007 was 4 h (IQR 2.3-6.0 hrs) and post 2010 was only 2.0 hr (IQR 1.5 to 3.1 hrs). The median amount ingested was 15 ml (IQR 10.0-50.0mls) prior to 2007 and 27.5mls (IQR 5.0-71.8mls) post 2010. In both studies most patients developed non-specific symptoms including nausea, vomiting, epigastric pain and headache. However, prior to 2007 only 1.9% of the cohort required mechanical ventilation due to respiratory failure and there were no reported deaths. In contrast, post 2010; deaths occurred in 3.0% of the cohort and 6.0% required mechanical ventilation for respiratory failure. The cause of mortality was due to one case of cardiorespiratory failure and the other due to a prolonged admission complicated with lobar pneumonia leading to decompensated liver failure on the background of undiagnosed liver cirrhosis.

CONCLUSION

Although acute exposure to imidacloprid is usually associated with mild non-specific symptoms, since the introduction of new formulations of imidacloprid, the toxic profile has changed with reported cases of death as well as an increase in cases requiring mechanical ventilation. The change in toxicity could be due to the solvents used in the newer formulations but also due to higher dose of imidacloprid described in our latter cohort. Further research into these solvents needs to be done and continued toxicovigilance is required.

Severe acute kidney injury following Sri Lankan Hypnale spp. envenoming is associated with thrombotic microangiopathy

CONTEXT

Acute kidney injury (AKI) is the most serious clinical manifestation of the Sri Lankan hump-nosed pit viper (Hypnale spp.) bites. Thrombotic microangiopathy (TMA) is increasingly recognized in association with AKI in cases of Hypnale spp envenomation. We investigated AKI in a cohort of cases of Hypnale envenomation, its association with TMA and the early diagnostic value of common biomarkers for AKI occurring.

MATERIALS AND METHODS

We conducted a prospective observational study of suspected viper bites and included 103 confirmed cases of Hypnale envenomation, based on venom specific enzyme immunoassay of blood. AKI was defined using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Thrombotic microangiopathy was diagnosed based on thrombocytopenia (platelet count < 150,000 × 10³/μL) and microangiopathic haemolytic anaemia (MAHA). We investigated the diagnostic performance of creatinine, platelet count and INR for AKI within 4 h and 8 h post-bite by area under the receiver operator characteristic curve (AUC-ROC).

RESULTS

Ten patients developed AKI: seven AKI stage 1 and three AKI stage 3. Ten patients (10%) developed thrombocytopaenia while 11 (11%) had MAHA. All three AKI stage 3 had thrombocytopaenia and MAHA fulfilling the criteria for TMA. Two of them presented with oliguria/anuria and all three required haemodialysis. Serum creatinine within 4 h post-bite was the best predictor of AKI with AUC-ROC of 0.83 (95% CI: 0.67-0.99) and was no better within 8 h of the bite.

CONCLUSIONS

We found that AKI is uncommon in Hypnale spp. envenomation, but an important serious complication. Severe AKI was associated with TMA. A creatinine within 4 h post-bite was the best predictor of AKI.

Subacute and chronic neuropsychological sequalae of acute organophosphate pesticide self-poisoning: a prospective cohort study from Sri Lanka

CONTEXT

Some epidemiological evidence implicates acute organophosphate (OP) pesticide poisoning in long-term neurocognitive deficits. However, no study has prospectively followed up poisoned patients long-term from the time of intoxication. We aimed to determine whether clinically significant acute OP self-poisoning leads to subacute and chronic neurocognitive deficits, in a prospective follow up study.

METHODS

Employing Mini Mental State Examination, Digit Span and Cambridge Neuropsychological Test Automated Battery (CANTAB), we compared multiple cognitive functions in 222 patients hospitalized with acute OP pesticide self-poisoning with a control group of 52 patients hospitalized with paracetamol overdose, at three time points: on discharge following clinical recovery, 6 weeks and 6 months post-ingestion. Intergroup comparisons at each time point were done in multiple regression models, adjusting for sex, age, education and psychiatric comorbidities. OP within-group analysis was done to determine a dose-response relationship.

RESULTS

After adjusting for covariates, the OP poisoned group had significantly poorer working memory (Digit Span) and episodic memory (CANTAB Paired Associates Learning); impaired spatial planning (CANTAB Stocking of Cambridge); and slower response speed in the sustained attention task (CANTAB Rapid Visual Information Processing), in the post-discharge assessment. Only working memory and episodic memory measures were impaired in the OP group at 6 weeks, whereas no significant intergroup differences were observed at 6 months. The OP subgroup who had complete red cell acetylcholinesterase inhibition on admission had poorer episodic memory when tested post-discharge than those who had partial inhibition, but no significant subgroup differences were observed at 6 weeks or 6 months.

DISCUSSION

Acute OP pesticide poisoning may cause neuropsychological impairment that outlasts the cholinergic phase on a subacute time scale; but does not cause measurable chronic neuropsychological deficits.

Nephrotoxicity induced by the venom of Hypnale hypnale from Sri Lanka: Studies on isolated perfused rat kidney and renal tubular cell lines

The hump-nosed pit viper Hypnale hypnale is responsible for a high number of snakebite cases in southwestern India and Sri Lanka. Although most patients only develop local signs and symptoms of envenoming, there is a growing body of evidence indicating that these envenomings may be associated with systemic alterations, including acute kidney injury. In this study we evaluated the renal toxicity of H. hypnale venom by using a perfused isolated rat kidney system and by assessing cytotoxicity in two different renal tubular cell lines in culture. The venom caused alterations in several renal functional parameters, such as reduction on perfusion pressure, renal vascular resistance, and sodium and chloride tubular transport, whereas glomerular filtration rate and urinary flow initially decreased and then increased after venom perfusion. In addition, this venom was cytotoxic to proximal and distal renal tubular cells in culture, with predominance of necrosis over apoptosis. Moreover, the venom affected the mitochondrial membrane potential and induced an increment in reactive oxygen species in these cells. Taken together, our results demonstrate a nephrotoxic activity of H. hypnale venom in these experimental models, in agreement with clinical observations.

Two rare case reports of ingestion of ammonium hydroxide and novel study of gastrointestinal toxicity

OBJECTIVE

We report the only two adult cases of NH4OH ingestion described in literature at the Peradeniya Teaching Hospital in Sri Lanka. Both cases showed clinical evidence of gastrointestinal toxicity and using intestinal fatty acid binding protein (IFABP), a novel biomarker, we attempted to quantify the extent of enterocyte damage. Procalcitonin was also measured as a maker of bacterial sepsis to ascertain whether there was a link between enterocyte damage and infection secondary to bacterial translocation.

CASES

A 45-year-old, previously well man was brought in by family with a reduced level of consciousness after ingestion of an unknown quantity of industrial NH4OH (29% solution) with suicidal intent. Peak IFABP and procalcitonin levels were 1274 pg/mL and 2.0 ng/mL, respectively, 7.7 hours following presumed ingestion. A 23-year-old, previously well woman presented 24 hours after consuming 100 mL of NH4OH (5.4% solution) used as a cleaning product. She presented with ongoing vomiting and oropharyngeal pain. Her peak IFABP and procalcitonin levels were 865 pg/mL and 5.8 ng/mL, respectively, 27.2 hours following ingestion.

CONCLUSION

We report the only two adult cases of NH4OH ingestion and describe severe gastrointestinal damage both clinically and biochemically. IFABP, currently only a marker used in research settings, was elevated in both cases but only marginally below that of levels seen in mesenteric ischaemia (levels greater than 1300 pg/mL). The use of a marker for enterocyte damage especially in ingestion of caustic solutions can allow clinicians to monitor progress, predict complications and evaluate the need for further invasive procedures.

Albuminuria and other renal damage biomarkers detect acute kidney injury soon after acute ingestion of oxalic acid and potassium permanganate

BACKGROUND

Deliberate self-poisoning with a combination washing powder containing oxalic acid (H₂C₂O₄) and potassium permanganate (KMnO₄) is a significant medical problem in the Southern Province of Sri Lanka. Acute kidney injury (AKI) is a frequent consequence. Biomarkers for early diagnosis of nephrotoxicity could guide appropriate supportive therapies.

METHODS

We investigated the performance of three serum biomarkers and nine urinary biomarkers in 85 patients in an ongoing multicenter prospective cohort study in Sri Lanka exploring AKI following poisoning.

RESULTS

Sixty two (62/85, 73%) patients developed AKI (acute kidney injury network, AKIN, criteria). Early and rapid increases in serum creatinine (sCr) peaking on day 3 were observed in AKIN stage 2 and 3 patients. In these patients, serum cystatin C (sCysC) rose more gradually but also peaked on day 3. Biomarker concentrations (normalized to urinary creatinine) of urinary albumin (uAlbumin), clusterin (uClusterin), beta-2-microglobulin (uB2M), osteopontin (uOPN), neutrophil gelatinase-associated lipocalin (uNGAL) and kidney injury molecule-1 (uKIM-1) in the AKIN2/3 group increased above the 95th centile concentration of the healthy population. Within 8 h of ingestion, the normalized uAlbumin and sCysC predicted AKIN2/3 with respective area under receiver operating characteristic curve, AUC-ROC values, of 0.94 (95% CI 0.86-1.00) and 0.85 (95% CI 0.76-0.95).

CONCLUSIONS

Urinary albumin was the best performing AKI biomarker following ingestion of H₂C₂O₄/KMnO₄. This may reflect glomerular injury and/or proximal tubular injury. The urinary albumin concentrations observed in this study could generally be detected using albumin specific dipstick methods, easily available even in resource poor settings.

Determination of the sub-lethal nephrotoxic dose of Russell's viper (Daboia russelii) venom in Wistar rats

Wistar rats were administered increasing doses of Russell's viper venom (RVV; 0.025-0.4 mg/kg) intraperitoneally to investigate acute kidney injury (AKI) by measuring creatinine (1.5-fold increase in serum creatinine above baseline) and examining kidney histology. Approximately 50% of rats receiving 0.25-0.4 mg/kg venom died within 72 h. An increase in serum creatinine only occurred at a venom dose of 0.4 mg/kg, except in two rats. Acute tubular necrosis, glomerular necrosis, cortical necrosis and interstitial inflammation were observed at venom doses of ≥0.25 mg/kg in 12/36 rats. However, of those 12 rats only four survived to 48 h compared to the 24 rats not developing nephrotoxicity, in which 18 were alive at 48 h. There was poor correlation between histological nephrotoxicity and AKI based on creatinine measurement. The early death in rats with AKI makes this a poor model for studying RVV-induced AKI.

Investigating knowledge regarding antibiotics and antimicrobial resistance among pharmacy students in Sri Lankan universities

Background

Antimicrobial resistance (AMR) is a major challenge for global health care. Pharmacists play a key role in the health care setting to help support the quality use of medicines. The education, training, and experiences of pharmacy students have the potential to impact on patterns of antibiotic use in community and hospital settings. The aim of this study was to investigate antibiotic use, knowledge of antibiotics and AMR among undergraduate pharmacy students at Sri Lankan universities and to compare this between junior and senior pharmacy student groups.

Methods

A cross-sectional study was conducted at the six universities in Sri Lanka that offer pharmacy undergraduate programmes. All pharmacy students in each university were invited to participate in this study using a self-administered questionnaire with ethics approval. The study instrument comprised five major sections: demographic information, self-reported antibiotic use, knowledge of antibiotic uses in human health, knowledge of AMR and antibiotic use in agriculture. Descriptive data analyses were conducted and Chi-squared analysis was used to explore associations between different variables and level of pharmacy education.

Results

Four hundred sixty-six pharmacy students completed the questionnaire. A majority of participants (76%) reported antibiotic use in the past year. More than half (57%) of the junior pharmacy students incorrectly indicated that antibiotic use is appropriate for the management of cold and flu conditions. Senior pharmacy students (n = 206) reported significantly better antibiotic knowledge than junior students (n = 260), p < 0.05. Overall pharmacy students showed good understanding of AMR and their knowledge level increased as the year of pharmacy study increased.

Conclusions

This study found that pharmacy students commonly report using antibiotics. Junior students report some misconceptions about antimicrobials. A comparison between junior and senior pharmacy students suggests that pharmacy education is associated with improved understanding of appropriate antibiotic use and AMR among undergraduate pharmacy students in Sri Lanka.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3107-8) contains supplementary material, which is available to authorized users.

Effectiveness of household lockable pesticide storage to reduce pesticide self-poisoning in rural Asia: a community-based, cluster-randomised controlled trial

BACKGROUND

Agricultural pesticide self-poisoning is a major public health problem in rural Asia. The use of safer household pesticide storage has been promoted to prevent deaths, but there is no evidence of effectiveness. We aimed to test the effectiveness of lockable household containers for prevention of pesticide self-poisoning.

METHODS

We did a community-based, cluster-randomised controlled trial in a rural area of North Central Province, Sri Lanka. Clusters of households were randomly assigned (1:1), with a sequence computer-generated by a minimisation process, to intervention or usual practice (control) groups. Intervention households that had farmed or had used or stored pesticide in the preceding agricultural season were given a lockable storage container. Further promotion of use of the containers was restricted to community posters and 6-monthly reminders during routine community meetings. The primary outcome was incidence of pesticide self-poisoning in people aged 14 years or older during 3 years of follow-up. Identification of outcome events was done by staff who were unaware of group allocation. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT1146496.

FINDINGS

Between Dec 31, 2010, and Feb 2, 2013, we randomly assigned 90 rural villages to the intervention group and 90 to the control group. 27 091 households (114 168 individuals) in the intervention group and 26 291 households (109 693 individuals) in the control group consented to participate. 20 457 household pesticide storage containers were distributed. In individuals aged 14 years or older, 611 cases of pesticide self-poisoning had occurred by 3 years in the intervention group compared with 641 cases in the control group; incidence of pesticide self-poisoning did not differ between groups (293·3 per 100 000 person-years of follow-up in the intervention group vs 318·0 per 100 000 in the control group; rate ratio [RR] 0·93, 95% CI 0·80-1·08; p=0·33). We found no evidence of switching from pesticide self-poisoning to other forms of self-harm, with no significant difference in the number of fatal (82 in the intervention group vs 67 in the control group; RR 1·22, 0·88-1·68]) or non-fatal (1135 vs 1153; RR 0·97, 0·86-1·08) self-harm events involving all methods.

INTERPRETATION

We found no evidence that means reduction through improved household pesticide storage reduces pesticide self-poisoning. Other approaches, particularly removal of highly hazardous pesticides from agricultural practice, are likely to be more effective for suicide prevention in rural Asia.

FUNDING

Wellcome Trust, with additional support from the American Foundation for Suicide Prevention, Lister Institute of Preventive Medicine, Chief Scientist Office of Scotland, University of Copenhagen, and NHMRC Australia.

Activated charcoal significantly reduces the amount of colchicine released from Gloriosa superba in simulated gastric and intestinal media

BACKGROUND

Poisoning with Gloriosa superba, a plant containing colchicine, is common in Sri Lanka.

OBJECTIVES

This study was to estimate release of colchicine from 5 g of different parts of Gloriosa superba in simulated gastric and intestinal media, and examine the binding efficacy of activated charcoal (AC) to colchicine within this model.

METHODS

A USP dissolution apparatus-II was used to prepare samples for analysis of colchicine using HPLC.

RESULTS

Cumulative colchicine release from tuber in gastric media at 120 minutes was significantly higher (2883 μg/g) than in intestinal media (1015 μg/g) (p < .001). Mean ± SD cumulative colchicine concentration over 2 hours from tuber, leaves and trunk in gastric medium was 2883.15 ± 1295.63, 578.25 ± 366.26 and 345.60 ± 200.08 μg/g respectively and the release in intestinal media was 1014.75 ± 268.16, 347.40 ± 262.61 and 251.55 ± 285.72 μg/g respectively. Introduction of 50 g of AC into both media made colchicine undetectable (<0.1 μg/ml).

CONCLUSIONS

The tuber released the highest quantity of colchicine. The colchicine release and elapse time to achieve saturated, equilibrium dissolution mainly depends on physicochemical properties of plant part. Significant in vitro binding of colchicine to AC suggests that AC has a role in decontamination of patients presenting to hospital after ingestion of Gloriosa superba.

Nephrotoxicity-induced proteinuria increases biomarker diagnostic thresholds in acute kidney injury

BACKGROUND

Paraquat ingestion is frequently fatal. While biomarkers of kidney damage increase during paraquat-induced acute kidney injury (AKI), significant concurrent proteinuria may alter diagnostic thresholds for diagnosis and prognosis to an unknown extent. This study evaluated the effect of albuminuria on biomarker cutoffs for diagnosis and outcome prediction.

METHODS

This was a multi-centre prospective clinical study of patients following acute paraquat self-poisoning in 5 Sri Lankan hospitals. Biomarker concentrations were quantified using ELISA and microbead assays and correlated with urinary albumin. Functional-AKI was defined by the Acute Kidney Injury Network serum creatinine definition and alternatively by a ≥50% increase in serum cystatin C. Albuminuria was defined as albumin-creatinine ratio >30 mg/g. The study outcomes were compared with a retrospective analysis of a pre-clinical study of paraquat-induced nephrotoxicity with appropriate controls.

RESULTS

Albuminuria was detected in 34 of 50 patients, and increased with functional-AKI severity. The concentrations of uNGAL, uCysC, uClusterin, uβ2M, and uKIM-1 were higher in albuminuric compared to non-albuminuric patients (p < 0.001). Albuminuria correlated with biomarker concentration (r > 0.6, p < 0.01) and was associated with death (p = 0.006). Optimal biomarker cutoffs for prediction of death were higher in the albuminuric group. Similar outcomes with more detailed analysis were obtained in experimental paraquat nephrotoxicity.

CONCLUSION

Albuminuria was associated with paraquat-induced nephrotoxicity and increased excretion of low-molecular weight protein biomarkers. AKI biomarker cutoffs for diagnosis, outcome prediction and AKI stratification increased in the presence of albuminuria. This may lead to over-diagnosis of AKI in conditions independently associated with proteinuria.

A randomized controlled trial of fresh frozen plasma for coagulopathy in Russell's viper (Daboia russelii) envenoming

Essentials Russell's viper envenoming is a major health issue in South Asia and causes coagulopathy. We studied the effect of fresh frozen plasma and two antivenom doses on correcting coagulopathy. Fresh frozen plasma did not hasten recovery of coagulopathy. Low-dose antivenom did not worsen coagulopathy.

SUMMARY

Background Russell's viper (Daboia russelii) envenoming is a major health issue in South Asia and causes venom-induced consumption coagulopathy (VICC). Objectives To investigate the effects of fresh frozen plasma (FFP) and two antivenom doses in correcting VICC. Methods We undertook an open-label randomized controlled trial in patients with VICC at two Sri Lankan hospitals. Patients with suspected Russell's viper bites and coagulopathy were randomly allocated (1 : 1) to high-dose antivenom (20 vials) or low-dose antivenom (10 vials) plus 4 U of FFP. The primary outcome was the proportion of patients with an International Normalized Ratio (INR) of < 2 at 6 h after antivenom administration. Secondary outcomes included anaphylaxis, major hemorrhage, death, and clotting factor recovery. Results From 214 eligible patients, 141 were randomized: 71 to high-dose antivenom, and 70 to low-dose antivenom/FFP; five had no post-antivenom blood tests. The groups were similar except for a delay of 1 h in antivenom administration for FFP patients. Six hours after antivenom administration, 23 of 69 (33%) patients allocated to high-dose antivenom had an INR of < 2, as compared with 28 of 67 (42%) allocated to low-dose antivenom/FFP (absolute difference 8%; 95% confidence interval - 8% to 25%). Fifteen patients allocated to FFP did not receive it. Severe anaphylaxis occurred equally frequently in each group. One patient given FFP developed transfusion-related acute lung injury. Three deaths occurred in low-dose antivenom/FFP patients, including one intracranial hemorrhage. There was no difference in recovery rates of INR or fibrinogen, but there was more rapid initial recovery of factor V and FX in FFP patients. Conclusion FFP after antivenom administration in patients with Russell's viper bites did not hasten recovery of coagulopathy. Low-dose antivenom/FFP did not worsen VICC, suggesting that low-dose antivenom is sufficient.

Is socioeconomic position associated with risk of attempted suicide in rural Sri Lanka? A cross-sectional study of 165 000 individuals

BACKGROUND

Lower socioeconomic position (SEP) is associated with an increased risk of suicidal behaviour in high-income countries, but this association is unclear in low-income and middle-income countries.

METHODS

We investigated the association of SEP with attempted suicide in a cross-sectional survey of 165 233 Sri Lankans. SEP data were collected at the household (assets, social standing (highest occupation of a household member), foreign employment and young (≤40 years) female-headed households) and individual level (education and occupation). Respondent-reported data on suicide attempts in the past year were recorded. Random-effects logistic regression models, accounting for clustering, were used to investigate the association of SEP with attempted suicide.

RESULTS

Households reported 398 attempted suicides in the preceding year (239 per 100 000). Fewer assets (OR 3.2, 95% CI 2.4 to 4.4) and having a daily wage labourer (ie, insecure/low-income job; OR 2.3, 95% CI 1.6 to 3.2) as the highest occupation increased the risk of an attempted suicide within households. At an individual level, daily wage labourers were at an increased risk of attempted suicide compared with farmers. The strongest associations were with low levels of education (OR 4.6, 95% CI 2.5 to 8.4), with a stronger association in men than women.

CONCLUSIONS

We found that indicators of lower SEP are associated with increased risk of attempted suicide in rural Sri Lanka. Longitudinal studies with objective measures of suicide attempts are needed to confirm this association.

TRIAL REGISTRATION NUMBER

NCT01146496; Pre-results.

Mechanism-specific injury biomarkers predict nephrotoxicity early following glyphosate surfactant herbicide (GPSH) poisoning

Acute kidney injury (AKI) is common following glyphosate surfactant herbicide (GPSH) self-poisoning. Serum creatinine (sCr) is the most widely used renal biomarker for diagnosis of AKI although a recent study in rats suggested that urinary kidney injury molecule-1 predicted AKI earlier and better after GPSH-induced nephrotoxicity. We explored the utility of a panel of biomarkers to diagnose GPSH-induced nephrotoxicity in humans. In a prospective multi-centre observational study, serial urine and blood samples were collected until discharge and at follow-up. The diagnostic performance of each biomarker at various time points was assessed. AKI was diagnosed using the Acute Kidney Injury Network (AKIN) definitions. The added value of each biomarker to sCr to diagnose AKI was assessed by the integrated discrimination improvement (IDI) metric. Of 90 symptomatic patients, 51% developed AKI and 5 patients who developed AKIN≥2 died. Increased sCr at 8 and 16h predicted moderate to severe AKI and death. None of the 10 urinary biomarkers tested increased above normal range in patients who did not develop AKI or had mild AKI (AKIN1); most of these patients also had only minor clinical toxicity. Absolute concentrations of serum and urinary cystatin C, urinary interleukin-18 (IL-18), Cytochrome C (CytoC) and NGAL increased many fold within 8h in patients who developed AKIN≥2. Maximum 8 and 16h concentrations of these biomarkers showed an excellent diagnostic performance (AUC-ROC ≥0.8) to diagnose AKIN≥2. However, of these biomarkers only uCytoC added value to sCr to diagnose AKI when assessed by IDI metrics. GPSH-induced nephrotoxicity can be diagnosed within 24h by sCr. Increases in uCytoC and uIL-18 confirm GPSH-induces apoptosis and causes mitochondrial toxicity. Use of these biomarkers may help to identify mechanism specific targeted therapies for GPSH nephrotoxicity in clinical trials.

High lethality and minimal variation after acute self-poisoning with carbamate insecticides in Sri Lanka - implications for global suicide prevention

Background: Highly hazardous organophosphorus (OP) insecticides are responsible for most pesticide poisoning deaths. As they are removed from agricultural practice, they are often replaced by carbamate insecticides of perceived lower toxicity. However, relatively little is known about poisoning with these insecticides.

Methods: We prospectively studied 1288 patients self-poisoned with carbamate insecticides admitted to six Sri Lankan hospitals. Clinical outcomes were recorded for each patient and plasma carbamate concentration measured in a sample to confirm the carbamate ingested.

Findings: Patients had ingested 3% carbofuran powder (719), carbosulfan EC25 liquid (25% w/v, 389), or fenobucarb EC50 liquid (50% w/v, 127) formulations, carbamate insecticides of WHO Toxicity Classes Ib, II, and II, respectively. Intubation and ventilation was required for 183 (14.2%) patients while 71 (5.5%) died. Compared with carbofuran, poisoning with carbosulfan or fenobucarb was associated with significantly higher risk of death [carbofuran 2.2%; carbosulfan 11.1%, OR 5.5 (95% CI 3.0–9.8); fenobucarb 6.3%, OR 3.0 (1.2–7.1)] and intubation [carbofuran 6.1%; carbosulfan 27.0%, OR 5.7 (3.9–8.3); fenobucarb 18.9%, OR 3.6 (2.1–6.1)]. The clinical presentation and cause of death did not differ markedly between carbamates. Median time to death was similar: carbofuran 42.3 h (IQR 5.5–67.3), carbosulfan 21.3 h (11.5–71.3), and fenobucarb 25.3 h (17.3–72.1) (p = 0.99); no patients showed delayed onset of toxicity akin to the intermediate syndrome seen after OP insecticide poisoning. For survivors, median duration of intubation was 67.8 h (IQR 27.5–118.8) with no difference in duration between carbamates. Reduced GCS at presentation was associated with worse outcome although some patients with carbosulfan died after presentation with normal GCS.

Conclusions: We did not find carbamate insecticide self-poisoning to vary markedly according to the carbamate ingested although the case fatality varied according to the concentration and formulation of the insecticide. Carbamate poisoning did not appear to be much less toxic than poisoning with some liquid OP insecticide formulations, e.g., chlorpyrifos EC40, that we have previously noted in these same hospitals (Lancet 2005, 366:1452–1459; QJM 2006, 99:513–522). Replacement of WHO Class II Toxicity OP insecticides in agriculture with high-strength liquid carbamate formulations may not substantially reduce case fatality after pesticide poisoning and, therefore, global suicide rates.

Prediction of paraquat exposure and toxicity in clinically ill poisoned patients: a model based approach

AIMS

Paraquat poisoning is a medical problem in many parts of Asia and the Pacific. The mortality rate is extremely high as there is no effective treatment. We analyzed data collected during an ongoing cohort study on self-poisoning and from a randomized controlled trial assessing the efficacy of immunosuppressive therapy in hospitalized paraquat-intoxicated patients. The aim of this analysis was to characterize the toxicokinetics and toxicodynamics of paraquat in this population.

METHODS

A non-linear mixed effects approach was used to perform a toxicokinetic/toxicodynamic population analysis in a cohort of 78 patients.

RESULTS

The paraquat plasma concentrations were best fitted by a two compartment toxicokinetic structural model with first order absorption and first order elimination. Changes in renal function were used for the assessment of paraquat toxicodynamics. The estimates of toxicokinetic parameters for the apparent clearance, the apparent volume of distribution and elimination half-life were 1.17 l h(-1) , 2.4 l kg(-1) and 87 h, respectively. Renal function, namely creatinine clearance, was the most significant covariate to explain between patient variability in paraquat clearance.This model suggested that a reduction in paraquat clearance occurred within 24 to 48 h after poison ingestion, and afterwards the clearance was constant over time. The model estimated that a paraquat concentration of 429 μg l(-1) caused 50% of maximum renal toxicity. The immunosuppressive therapy tested during this study was associated with only 8% improvement of renal function.

CONCLUSION

The developed models may be useful as prognostic tools to predict patient outcome based on patient characteristics on admission and to assess drug effectiveness during antidote drug development.

Population Pharmacokinetics of an Indian F(ab')2 Snake Antivenom in Patients with Russell's Viper (Daboia russelii) Bites

BACKGROUND

There is limited information on antivenom pharmacokinetics. This study aimed to investigate the pharmacokinetics of an Indian snake antivenom in humans with Russell's viper bites.

METHODS/PRINCIPAL FINDINGS

Patient data and serial blood samples were collected from patients with Russell's viper (Daboia russelii) envenoming in Sri Lanka. All patients received Indian F(ab')2 snake antivenom manufactured by VINS Bioproducts Ltd. Antivenom concentrations were measured with sandwich enzyme immunoassays. Timed antivenom concentrations were analysed using MONOLIXvs4.2. One, two and three compartment models with zero order input and first order elimination kinetics were assessed. Models were parameterized with clearance (CL), intercompartmental clearance (Q), central compartment volume (V) and peripheral compartment volume (VP). Between-subject-variability (BSV) on relative bioavailability (F) was included to account for dose variations. Covariates effects (age, sex, weight, antivenom batch, pre-antivenom concentrations) were explored by visual inspection and in model building. There were 75 patients, median age 57 years (40-70 y) and 64 (85%) were male. 411 antivenom concentration data points were analysed. A two compartment model with zero order input, linear elimination kinetics and a combined error model best described the data. Inclusion of BSV on F and weight as a covariate on V improved the model. Inclusion of pre-antivenom concentrations or different batches on BSV of F did not. Final model parameter estimates were CL,0.078 L h(-1), V,2.2L, Q,0.178 L h(-1) and VP,8.33L. The median half-life of distribution was 4.6 h (10-90%iles:2.6-7.1 h) and half-life of elimination, 140 h (10th-90th percentilesx:95-223h).

CONCLUSION

Indian F(ab')2 snake antivenom displayed biexponential disposition pharmacokinetics, with a rapid distribution half-life and more prolonged elimination half-life.

Epidemiology and clinical effects of hump-nosed pit viper (Genus: Hypnale) envenoming in Sri Lanka

Hump-nosed pit vipers of Genus Hypnale are the commonest cause of snake bite in Sri Lanka. Although there are many reports of local effects, coagulopathy and acute kidney injury, it remains unclear how frequent these clinical effects are and therefore the medical importance of this snake genus. The genus has been recently revised to include Hypnale hypnale from Sri Lanka and Western Ghats of Southern India, and the two endemic species to Sri Lanka, Hypnale zara and Hypnale nepa. This was a prospective hospital-based clinical study of definite Hypnale spp. bites from July 2008 to July 2010 in six Sri Lankan hospitals. There were 114 patients included and all snakes were correctly identified by hospital staff as Hypnale spp. Of these, 93 snakes were identified as H. hypnale by an expert, 16 as H. zara and five as H. nepa. Most bites occurred on the lower limbs in the daytime. There was no difference in the clinical effects between the three species. Pain and fang marks were present in all patients, 101 had local swelling and only 16 (14%) developed extensive local swelling that spread proximally and involved more than half of the bitten limb. Systemic symptoms occurred in 18 patients; four patients had an abnormal 20 min whole blood clotting test and one patient developed an acute kidney injury that required haemodialysis. All patients were discharged alive with a median length of stay of 2 days. This study confirms that hump-nosed viper bites cause only minor effects in most cases. Future studies need to undertake formal coagulation studies and identify important early indicators of renal impairment.

Comparative in-vivo toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Crotalinae: Hypnale)

Background

Envenoming by south Asian hump-nosed pit vipers (Genus: Hypnale) is a significant health issue in Sri Lanka and in peninsular India. Bites by these snakes frequently lead to local envenoming, coagulopathy and acute renal failure even resulting in death. Recently the genus was revised and the existence of three species viz H. hypnale, H. nepa and H. zara were recognized. There is, however, a paucity of information on the toxicity of the venoms of these species. Hence, we compared the toxic effects of the three Hypnale venoms using BALB/c mice.

Findings

Intraperitoneal median lethal doses (LD₅₀) for H. hypnale, H. zara and H. nepa venoms were 1.6, 6.0 and 9.5 μg protein/g respectively. Minimum haemorrhagic doses for venoms of H. hypnale, H. zara and H. nepa were 3.4, 11.0 and 16.6 μg protein/mouse respectively. The minimum necrotic doses for the same venoms were 15.0, 55.1 and 68.2 μg protein/mouse respectively. Severe congestion and petecheal haemorrhages were observed in lungs, kidneys, liver and the alimentary tract. Histopathogical examination of kidneys revealed proximal tubular cell injury and acute tubular necrosis with intact basement membrane indicating possible direct nephrotoxicity. Hypnale venoms caused pulmonary oedema, hepatocellular degeneration and necrosis, focal neuronal degeneration in brain and extramedullary haemopoiesis in spleen. H. hypnale venom caused all above histopathological alterations at lower doses compared to the other two.

Conclusion

Hypnale venoms cause similar pathological changes with marked differences in the severity of the toxic effects in vivo. Therefore, differences in the severity of the clinical manifestations could possibly be seen among bite victims of the three Hypnale species.

A community-based cluster randomised trial of safe storage to reduce pesticide self-poisoning in rural Sri Lanka: study protocol

Background

The WHO recognises pesticide poisoning to be the single most important means of suicide globally. Pesticide self-poisoning is a major public health and clinical problem in rural Asia, where it has led to case fatality ratios 20-30 times higher than self-poisoning in the developed world. One approach to reducing access to pesticides is for households to store pesticides in lockable "safe-storage" containers. However, before this approach can be promoted, evidence is required on its effectiveness and safety.

Methods/Design

A community-based cluster randomised controlled trial has been set up in 44,000 households in the North Central Province, Sri Lanka. A census is being performed, collecting baseline demographic data, socio-economic status, pesticide usage, self-harm and alcohol. Participating villages are then randomised and eligible households in the intervention arm given a lockable safe storage container for agrochemicals.

The primary outcome will be incidence of pesticide self-poisoning over three years amongst individuals aged 14 years and over. 217,944 person years of follow-up are required in each arm to detect a 33% reduction in pesticide self-poisoning with 80% power at the 5% significance level. Secondary outcomes will include the incidence of all pesticide poisoning and total self-harm.

Discussion

This paper describes a large effectiveness study of a community intervention to reduce the burden of intentional poisoning in rural Sri Lanka. The study builds on a strong partnership between provincial health services, local and international researchers, and local communities. We discuss issues in relation to randomisation and contamination, engaging control villages, the intervention, and strategies to improve adherence.

Trial Registritation

The trial is registered on ClinicalTrials.gov ref: NCT1146496 (http://clinicaltrialsfeeds.org/clinical-trials/show/NCT01146496).

Simple and sensitive liquid chromatography-tandem mass spectrometry methods for quantification of paraquat in plasma and urine: application to experimental and clinical toxicological studies

Simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods have been developed and validated for quantification of paraquat (PQ) in plasma and urine. Plasma and urine sample preparation were carried out by one-step protein precipitation using cold acetonitrile (-20 to -10 °C). After centrifugation, an aliquot of 10 μL of supernatant was injected into a Kinetex™ hydrophilic interaction chromatography (HILIC) column with a KrudKatcher™ Ultra in-line filter. The chromatographic separation was achieved using the mobile phase mixture of 250 mM ammonium formate (with 0.8% aqueous formic acid) in water and acetonitrile at a flow rate of 0.3 mL/min. Detection was performed using an API2000 triple quadrupole tandem mass spectrometer in multiple reaction monitoring (MRM) mode via an electrospray ionization (ESI) source. The calibration curve was linear over the concentration range of 10-5000 ng/mL, with an LLOQ of 10 ng/mL. The inter- and intra-day precision (% R.S.D.) were <8.5% and 6.4% for plasma and urine, respectively with the accuracies (%) within the range of 95.1-102.8%. PQ in plasma and urine samples was stable when stored at -70 °C for three freeze-thaw cycles. The methods were successfully applied to determine PQ concentration in rat and human samples.

The in vitro toxicity of venoms from South Asian hump-nosed pit vipers (Viperidae: Hypnale)

Hump-nosed pit vipers (Genus Hypnale) are venomous snakes from South India and Sri Lanka. Envenoming by Hypnale species may cause significant morbidity and is characterized by local envenoming and less commonly coagulopathy and acute renal failure. Currently there are three nominal species of this genus: H. hypnale, H. zara and H. nepa. This study investigates the biochemical and pharmacological properties of the venoms from the three Hypnale species in Sri Lanka. The three Hypnale venoms had similar chromatographic profiles using reverse phase high performance liquid chromatography and fractions with procoagulant activity were identified. Hypnale venoms had potent cytotoxicity in cultured rat aorta smooth muscle cells with similar IC(50) values. The venoms had weak neurotoxic and myotoxic activity in the isolated chick biventer muscle preparation. They had mild procoagulant activity with close MCC(5) values and also phospholipase activity. Locally available polyvalent antivenom did not neutralise any venom effects. The study demonstrates that the three Hypnale venoms are similar and cytotoxicity appears to be the most potent effect, although they have mild procoagulant activity. These findings are consistent with clinical reports.

Acute human lethal toxicity of agricultural pesticides: a prospective cohort study

BACKGROUND

agricultural pesticide poisoning is a major public health problem in the developing world, killing at least 250,000-370,000 people each year. Targeted pesticide restrictions in Sri Lanka over the last 20 years have reduced pesticide deaths by 50% without decreasing agricultural output. However, regulatory decisions have thus far not been based on the human toxicity of formulated agricultural pesticides but on the surrogate of rat toxicity using pure unformulated pesticides. We aimed to determine the relative human toxicity of formulated agricultural pesticides to improve the effectiveness of regulatory policy.

METHODS AND FINDINGS

we examined the case fatality of different agricultural pesticides in a prospective cohort of patients presenting with pesticide self-poisoning to two clinical trial centers from April 2002 to November 2008. Identification of the pesticide ingested was based on history or positive identification of the container. A single pesticide was ingested by 9,302 patients. A specific pesticide was identified in 7,461 patients; 1,841 ingested an unknown pesticide. In a subset of 808 patients, the history of ingestion was confirmed by laboratory analysis in 95% of patients. There was a large variation in case fatality between pesticides-from 0% to 42%. This marked variation in lethality was observed for compounds within the same chemical and/or WHO toxicity classification of pesticides and for those used for similar agricultural indications.

CONCLUSION

the human data provided toxicity rankings for some pesticides that contrasted strongly with the WHO toxicity classification based on rat toxicity. Basing regulation on human toxicity will make pesticide poisoning less hazardous, preventing hundreds of thousands of deaths globally without compromising agricultural needs. Ongoing monitoring of patterns of use and clinical toxicity for new pesticides is needed to identify highly toxic pesticides in a timely manner.

Fructose-1, 6-diphosphate (FDP) as a novel antidote for yellow oleander-induced cardiac toxicity: a randomized controlled double blind study

BACKGROUND

Cardiac toxicity due to ingestion of oleander plant seeds in Sri Lanka and some other South Asian countries is very common. At present symptomatic oleander seed poisoning carries a mortality of 10% in Sri Lanka and treatment of yellow oleander poisoning is limited to gastric decontamination and atropine administration. The only proven effective antidote is digoxin antibodies but these are not available for routine use because of the high cost. The main objective of this study is to investigate the effectiveness of a new and inexpensive antidote for patients with life threatening arrhythmias due oleander poisoning.

METHOD/DESIGN

We set up a randomised double blind clinical trial to assess the effectiveness of Fructose 1, 6 diphosphate (FDP) in acute yellow oleander poisoning patients admitted to the adult medical wards of a tertiary hospital in Sri Lanka. Patients will be initially resuscitated following the national guidelines and eligible patients will be randomised to receive either FDP or an equal amount of normal saline. The primary outcome measure for this study is the sustained reversion to sinus rhythm with a heart rate greater than 50/min within 2 hours of completion of FDP/placebo bolus. Secondary outcomes include death, reversal of hyperkalaemia on the 6, 12, 18 and 24 hour samples and maintenance of sinus rhythm on the holter monitor. Analysis will be on intention-to-treat.

DISCUSSION

This trial will provide information on the effectiveness of FDP in yellow oleander poisoning. If FDP is effective in cardiac glycoside toxicity, it would provide substantial benefit to the patients in rural Asia. The drug is inexpensive and thus could be made available at primary care hospitals if proven to be effective.

TRIAL REGISTRATION

Current Controlled trial ISRCTN71018309.

Acute intentional self-poisoning with a herbicide product containing fenoxaprop-P-ethyl, ethoxysulfuron, and isoxadifen ethyl: a prospective observational study

BACKGROUND

Herbicides are commonly ingested for self-harm, but relatively little has been published on poisoning with herbicides other than paraquat and glyphosate. We report here a case series of patients with acute exposure to a combination herbicide (brand name Tiller Gold or Whip Super) containing the selective phenoxy herbicide compounds fenoxaprop-P-ethyl and ethoxysulfuron and a safener isoxadifen ethyl.

METHOD

Clinical data on all patients presenting with Tiller Gold or Whip Super poisoning to two General Hospitals in Sri Lanka from 2002-2008 were collected prospectively until discharge.

RESULTS

Eighty-six patients with a history of Tiller Gold or Whip Super ingestion were included. The main clinical features were an epigastric burning sensation and vomiting; however, most of those who vomited had received gastric lavage or forced emesis. Eight patients had a reduced level of consciousness on admission (Glasgow coma scale 9-14) that resolved without intervention over several hours. Only symptomatic and supportive care was required. The median hospital stay was 1 day (IQR: 1-2) and the case fatality was zero (95% confidence interval: 0-4.2%). This low case fatality compared favorably with the case fatality of other common herbicides in our cohort: paraquat >40%, propanil >10%, 4-chloro-2-methylphenoxyacetic acid > 5%, and glyphosate >2%.

CONCLUSION

This combination herbicide product appears to be safe in patients with acute self-poisoning, particularly in comparison with other herbicides, and causing few clinical features.

Systematic review of controlled clinical trials of gastric lavage in acute organophosphorus pesticide poisoning

BACKGROUND

Organophosphorus pesticide (OP) self-poisoning is a major problem in the developing rural world. There is little clinical trial data to guide therapy, hindering the identification of best therapy. Despite the recognition of adverse effects, gastric lavage is commonly done in Asia. We aimed to identify studies assessing its effectiveness.

METHOD

We systematically searched the literature for controlled clinical studies that assessed the effect of gastric lavage in OP pesticide self-poisoning.

RESULTS

All 56 studies identified were Chinese and reported benefit from the intervention studied, including multiple gastric lavages, use of norepinephrine or pralidoxime in the lavage fluid, concurrent treatment with naloxone or scopolamine, insertion of the gastric tube via a laparotomy incision, and lavage later than 12 h post-ingestion. However, only 23 were RCTs and none presented adequate methodology for their quality to be assessed. The patient population and study treatment protocol were not defined - large variation in case fatality in the control arm of the studies (from 4.5 to 93%) suggests marked variation between studies and likely between study arms. No study compared an intervention against a control group receiving no gastric lavage or provided any data to indicate whether a significant quantity of poison was removed.

CONCLUSION

Despite widespread use of multiple gastric lavages for OP pesticide poisoning across Asia, there is currently no high-quality evidence to support its clinical effectiveness. There is a need for studies to identify in which patients and for what duration gastric lavage is able to remove significant quantities of poison. Following these studies, large clinical trials will be required to address the effectiveness and safety of gastric lavage (either single or multiple) in acute OP pesticide poisoning.

Acute human self-poisoning with imidacloprid compound: a neonicotinoid insecticide

Background

Deliberate self-poisoning with older pesticides such as organophosphorus compounds are commonly fatal and a serious public health problem in the developing world. The clinical consequences of self-poisoning with newer pesticides are not well described. Such information may help to improve clinical management and inform pesticide regulators of their relative toxicity. This study reports the clinical outcomes and toxicokinetics of the neonicotinoid insecticide imidacloprid following acute self-poisoning in humans.

Methodology/Principal Findings

Demographic and clinical data were prospectively recorded in patients with imidacloprid exposure in three hospitals in Sri Lanka. Blood samples were collected when possible for quantification of imidacloprid concentration. There were 68 patients (61 self-ingestions and 7 dermal exposures) with exposure to imidacloprid. Of the self-poisoning patients, the median time to presentation was 4 hours (IQR 2.3–6.0) and median amount ingested was 15 mL (IQR 10–50 mL). Most patients only developed mild symptoms such as nausea, vomiting, headache and diarrhoea. One patient developed respiratory failure needing mechanical ventilation while another was admitted to intensive care due to prolonged sedation. There were no deaths. Median admission imidacloprid concentration was 10.58 ng/L; IQR: 3.84–15.58 ng/L, Range: 0.02–51.25 ng/L. Changes in the concentration of imidacloprid in serial blood samples were consistent with prolonged absorption and/or saturable elimination.

Conclusions

Imidacloprid generally demonstrates low human lethality even in large ingestions. Respiratory failure and reduced level of consciousness were the most serious complications, but these were uncommon. Substitution of imidacloprid for organophosphorus compounds in areas where the incidence of self-poisoning is high may help reduce deaths from self-poisoning.

Comparison of two commonly practiced atropinization regimens in acute organophosphorus and carbamate poisoning, doubling doses vs. ad hoc: a prospective observational study

There is a wide variation and lack of evidence in current recommendations for atropine dosing schedules leading to subsequent variation in clinical practice. Therefore, we sought to examine the safety and effectiveness of a titrated vs. ad hoc atropine treatment regimen in a cohort of patients with acute cholinesterase inhibitor pesticide poisoning. A prospective cohort study was conducted in three district secondary referral hospitals in Sri Lanka using a structured data collection form that collected details of clinical symptoms and outcomes of cholinesterase inhibitor pesticide poisoning, atropine doses, and signs of atropinization. We compared two hospitals that used a titrated dosing protocol based on a structured monitoring sheet for atropine infusion with another hospital using an ad hoc regime. During the study, 272 symptomatic patients with anticholinesterase poisoning requiring atropine were admitted to the three hospitals. Outcomes of death and ventilation were analyzed for all patients, 226 patients were prospectively assessed for atropine toxicity. At baseline, patients in the titrated dose cohort had clinical signs consistent with greater toxicity. This in part may be due to ingestion of more toxic organophosphates. They received less pralidoxime and atropine, and were less likely to develop features of atropine toxicity, such as delirium (1% vs. 17%), hallucinations (1% vs. 35%), or either (1% vs. 35%) and need for patient restraint (3% vs. 48%) compared with the ad hoc dose regime. After adjusting for the pesticides ingested, there was no difference in mortality and ventilatory rates between protocols. Ad hoc high dose atropine regimens are associated with more frequent atropine toxicity without any obvious improvement in patient outcome compared with doses titrated to clinical effect. Atropine doses should be titrated against response and toxicity. Further education and the use of a structured monitoring sheet may assist in more appropriate atropine use in anticholinesterase pesticide poisoning.