Outcomes of multicystic peritoneal mesothelioma treatment with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

BACKGROUND

Multicystic peritoneal mesothelioma (MCPM) is a rare neoplasm, generally considered a borderline malignancy, best treated by cytoreductive surgery (CRS) to remove macroscopic disease, combined with hyperthermic intraperitoneal chemotherapy (HIPEC). Owing to its rarity, little has been published on clinical presentation, clinical behaviour over time, or an optimal treatment approach.

METHODS

A prospectively developed peritoneal malignancy database was interrogated for the years 2001-2018. Details on all patients with MCPM as a definitive diagnosis after CRS and HIPEC were analysed, including previous interventions, mode of presentation, surgical treatment, postoperative outcomes, and late follow-up information from abdominal CT and tumour markers.

RESULTS

Some 40 patients with MCPM underwent CRS and HIPEC between 2001 and 2018. Of these, 32 presented with abdominal pain, distension or bloating, six patients presented with recurrence following previous surgery at the referring hospitals, and two had coincidental diagnoses during a surgical procedure. CRS involved peritonectomy in all 40 patients. Bowel resection was required in 18 patients, and seven had a temporary stoma. Thirty-eight patients were considered to have undergone a complete macroscopic tumour removal (completeness of cytoreduction CC0), and two had residual tumour nodules less than 2.5 mm in size, classified as CC1. Median duration of follow-up was 65 (range 48-79) months. There were no deaths during follow-up. The Kaplan-Meier-predicted recurrence-free interval was 115.4 months.

CONCLUSION

MCPM is a rare peritoneal neoplasm with a heterogeneous pattern of presentation. CRS and HIPEC is an effective management option for this group of patients, with favourable long-term survival.

Urinary versus serum microRNAs in human oxalic acid poisoning: Contrasting signals and performance

MicroRNAs are key regulators of the normal kidney function and development, and altered in acute kidney injury (AKI). However, there is a lack of studies comparing serum and urine miRNA expression in toxic AKI in humans. We aimed to compare the global signature of urinary and serum microRNAs, with and without kidney injury, after human oxalic acid poisoning. We profiled urinary microRNAs in patients who ingested oxalic acid and developed no injury (No AKI n = 3), moderate injury (AKIN2 n = 3) or severe injury (AKIN3 n = 3) and healthy controls (n = 3). We validated a signature of 30 urinary microRNAs identified in the discovery profiling, in a second cohort of individuals exposed to oxalic acid (No AKI n = 15, AKIN2 n=11 & AKIN3 n= 18) and healthy controls (n=-27) and we compared the results with previously published serum data. Global profiling in toxic AKI patients showed a higher expression of urinary microRNAs and lower expression of serum microRNAs. Most urine microRNA in the validation cohort were significantly upregulated (25/30, fold change >2.8 and p < 0.05) in AKIN2/3 patients compared to No AKI. Four urinary microRNAs (miR-191, miR-19b, miR-20a and miR-30b) had good diagnostic performance (AUC greater than 0.8) to predict AKIN2/3 between 4-8 hours post ingestion. Poisoning irrespective of AKI led to significantly lower expression of many microRNAs in serum but relatively few changes in urinary miRNA expression. In conclusion, urinary microRNA signature provides a stronger measure of AKI in oxalic acid poisoning compared to serum microRNA. Kidney injury has the greatest impact on urinary microRNA, while poisoning itself was better reflected in serum miRNA. Plasma and urinary microRNAs signatures provide complementary information in toxic kidney injury.

Cellular injury leading to oxidative stress in acute poisoning with potassium permanganate/oxalic acid, paraquat, and glyphosate surfactant herbicide

Previous studies on human acute kidney injury (AKI) following poisoning with potassium permanganate/oxalic acid (KMnO4/H2C2O4), paraquat, and glyphosate surfactant herbicide (GPSH) have shown rapid and large increases in serum creatinine (sCr) that cannot be entirely explained by direct nephrotoxicity. One plausible mechanism for a rapid increase in sCr is oxidative stress. Thus, we aimed to explore biomarkers of oxidative stress, cellular injury, and their relationship with sCr, after acute KMnO4/H2C2O4, paraquat, and GPSH poisonings. Serum biomarkers [sCr, creatine (sCn), cystatin C (sCysC)] and urinary biomarkers [cytochrome C (CytoC), 8-isoprostane (8-IsoPs)] were evaluated in 105 patients [H2C2O4/KMnO4 (N = 57), paraquat, (N = 21), GPSH (N = 27)] recruited to a multicenter cohort study. We used area under the receiver operating characteristics curve (AUC-ROC) to quantify the extent of prediction of moderate to severe AKI (acute kidney injury network stage 2/3 (AKIN2/3)). Patients with AKIN2/3 showed increased levels of CytoC. Early high CytoC predicted AKIN2/3 in poisoning with KMnO4/H2C2O4 (AUC-ROC4-8h: 0.81), paraquat (AUC-ROC4-8h: 1.00), and GPSH (AUC-ROC4-8h: 0.91). 8-Isoprostane levels were not significantly elevated. Reduced sCn and increased sCr/sCn ratios were observed for 48 h post KMnO4/H2C2O4 ingestion. Paraquat exhibited a similar pattern (N = 11), however only 3 were included in our study. Increased CytoC suggests there is mitochondrial injury coupled with energy depletion. The increased sCr within 24 h could be due to increased conversion of cellular creatine to creatinine during the process of adenosine triphosphate (ATP) generation and then efflux from cells. Later increases of sCr are more likely to represent a true decrease in kidney function.

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.

Clinical and surgical outcomes of patients with peritoneal mesothelioma discussed at a monthly national multidisciplinary team video-conference meeting

Background

Peritoneal mesothelioma (PM) is a rare primary neoplasm of the peritoneum with an increasing incidence worldwide. Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has shown promise as a treatment strategy. A national PM multidisciplinary team (national PM MDT) video‐conference meeting was established in the UK and Ireland in March 2016, aiming to plan optimal treatment, record outcomes and provide evidence for the benefits of centralization. This article reports on the activities and outcomes of the first 2·5 years.

Methods

Between March 2016 and December 2018, patients with PM, referred to peritoneal malignancy centres in Basingstoke, Birmingham, Manchester and Dublin, were discussed by the national PM MDT via video‐conference. The MDT was composed of surgeons, radiologists, specialist nurses and pathologists. Patients were considered for CRS and HIPEC if considered fit for surgery and if radiological imaging suggested that complete surgical cytoreduction could be achieved. Morbidity and mortality following surgery were analysed. Survival analysis following MDT discussion was conducted.

Results

A total of 155 patients (M : F ratio 0·96) with a mean(s.d.) age of 57(17) years were discussed. To date, 22 (14·2 per cent) have had CRS and HIPEC; the median Peritoneal Cancer Index for the surgical group was 17·0. Complete cytoreduction was achieved in 19 patients. Clavien–Dindo grade I–II complications occurred in 16 patients; there was no grade III–IV morbidity or 30‐day in‐hospital mortality. The median follow‐up for the whole cohort was 18·7 months, and the 2‐year survival rate from time of first review at the national PM MDT was 68·3 per cent.

Conclusion

The centralized national PM MDT was effective at selecting patients suitable for CRS and HIPEC, reporting a good outcome from patient selection.

An LC-MS/MS method for creatine and creatinine analysis in paraquat-intoxicated patients

A sudden increase in serum creatinine after paraquat intoxication has been reported in several clinical studies. However, this dramatic change of creatinine may be possibly due to an interconversion of creatine-creatinine in relation to paraquat toxicity. In order to investigate the creatine-creatinine relationship, a liquid chromatography tandem mass spectrometry in combination with electrospray ionization was developed and validated for simultaneous determination of creatine and creatinine in the serum. The chromatographic separation was achieved on a Gemini® C₆-Phenyl column with a gradient elution consisting of 0.1% formic acid in ultrapure water and methanol as the mobile phase. The method yielded suitable levels of specificity and selectivity, and calibration curves of creatine and creatinine in serum were linear over the concentration range of 0.5-200 µg mL^-1. The limit of quantification of both compounds was 0.5 µg mL^-1, and the method was accurate within the recovery range of 96.23-102.75%, indicating the robustness of the method. The method was successfully applied to toxicological samples from paraquat-intoxicated patients, and the concentrations of creatine and creatinine were quantified. High creatine concentrations in serum samples were observed which may lead to high serum creatinine despite normal kidney function as creatine is converted to creatinine in proportion to its concentration.

Early identification of acute kidney injury in Russell's viper (Daboia russelii) envenoming using renal biomarkers

BACKGROUND

Acute kidney injury (AKI) is a major complication of snake envenoming, but early diagnosis remains problematic. We aimed to investigate the time course of novel renal biomarkers in AKI following Russell's viper (Daboia russelii) bites.

METHODOLOGY/PRINCIPAL FINDINGS

We recruited a cohort of patients with definite Russell's viper envenoming and collected serial blood and urine samples on admission (<4h post-bite), 4-8h, 8-16h, 16-24h, 1 month and 3 months post-bite. AKI stage (1-3) was defined using the Acute Kidney Injury Network criteria. AKI stages (1-3) were defined by the Acute Kidney Injury Network (AKIN) criteria. There were 65 Russell's viper envenomings and 49 developed AKI: 24 AKIN stage 1, 13 stage 2 and 12 stage 3. There was a significant correlation between venom concentrations and AKI stage (p = 0.007), and between AKI stage and six peak biomarker concentrations. Although most biomarker concentrations were elevated within 8h, no biomarker performed well in diagnosing AKI <4h post-bite. Three biomarkers were superior to serum creatinine (sCr) in predicting AKI (stage 2/3) 4-8h post-bite: serum cystatin C (sCysC) with an area under the receiver operating curve (AUC-ROC), 0.78 (95%CI:0.64-0.93), urine neutrophil gelatinase-associated lipocalin (uNGAL), 0.74 (95%CI:0.59-0.87) and urine clusterin (uClu), 0.81 (95%CI:0.69-0.93). No biomarker was better than sCr after 8h. Six other urine biomarkers urine albumin, urine beta2-microglobulin, urine kidney injury molecule-1, urine cystatin C, urine trefoil factor-3 and urine osteopontin either had minimal elevation, and/or minimal prediction for AKI stage 2/3 (AUC-ROC<0.7).

CONCLUSIONS/SIGNIFICANCE

AKI was common and sometimes severe following Russell's viper bites. Three biomarkers uClu, uNGAL and sCysC, appeared to become abnormal in AKI earlier than sCr, and may be useful in early identification of envenoming.

Paediatric poisoning in rural Sri Lanka: an epidemiological study

BACKGROUND

Acute paediatric poisoning is a common public health concern for both developed and developing countries. The type of agent and underlying cause differ depending on the social, cultural, economic and educational background. The objectives of this study were to identify the incidence and pattern of paediatric poisoning in a rural district in Sri Lanka and establish whether tertiary referral hospital data are a useful surrogate for estimating district level epidemiology of paediatric poisoning.

METHODS

A subset of epidemiological data were obtained from March 2011 to February 2013 from a randomized controlled trial (SLCTR/2010/008) conducted in 45 hospitals in Kurunegala district.

RESULTS

The age adjusted annual incidence of all cause of acute poisoning in children aged 1 to 12 years in the study area was 60.4 per 100,000. The incidence of poisoning of younger age group (1 to 6 years; 76 per 100,000) was significantly higher than older age group (7 to 12 years; 41 per 100,000) (p = 0.0001) in Kurunegala district. The annual incidence rate of paediatric admissions due to deliberate self-poisoning is 18 per 100,000 population. This study also established that admission data from primary hospitals provided the most accurate epidemiological information on paediatric poisoning.

CONCLUSIONS

In rural districts of Sri Lanka, acute paediatric poisoning cases were less frequent and less severe compared to adult poisoning cases (426-446 per 100,000 population). The incidence of poisoning was significantly higher among young children with compared to old children. In this study, deliberate self-poisoning among older children was more frequently seen than in other comparable countries. Because most of the admissions are directed to and managed by primary hospitals, data from referral hospitals alone cannot be used to represent the true incidence of acute poisoning within a district. The data set from all the primary hospitals (n = 44) yielded more accurate poisoning incidence amongst a paediatric population.

Biological mesh is a safe and effective method of abdominal wall reconstruction in cytoreductive surgery for peritoneal malignancy

Background

Patients with peritoneal malignancy often have multiple laparotomies before referral for cytoreductive surgery (CRS). Some have substantial abdominal wall herniation and tumour infiltration of abdominal incisions. CRS involves complete macroscopic tumour removal and hyperthermic intraperitoneal chemotherapy (HIPEC). Abdominal wall reconstruction is problematic in these patients. The aim of this study was to establish immediate and long-term outcomes of abdominal wall reconstruction with biological mesh in a single centre.

Methods

A dedicated peritoneal malignancy database was searched for all patients who had biological mesh abdominal wall reconstruction between 2004 and 2015. Short- and long-term outcomes were reviewed. All patients had annual abdominal CT as routine peritoneal malignancy follow-up.

Results

Some 33 patients (22 women) with a mean age of 53·4 (range 19-82) years underwent abdominal wall reconstruction with biological mesh. The majority (23) had CRS for pseudomyxoma (19 low grade), six for colorectal peritoneal metastasis and four for appendiceal adenocarcinoma; 18 had undergone CRS and HIPEC previously. Twenty-five of the 33 patients had abdominal wall tumour involvement and eight had concurrent hernias. The mean duration of surgery was 486 (range 120-795) min and the mean mesh size used was 345 (50-654) cm². Ten patients developed wound infections and four had a seroma. Two developed early enterocutaneous fistulas. Mean follow-up was 48 months. Five patients developed an incisional hernia. Four died from progressive malignancy. A further 15 patients had disease recurrence, but only one had isolated abdominal wall recurrence.

Conclusion

Biological mesh was safe and effective for abdominal wall reconstruction in peritoneal malignancy. Postoperative wound infections were frequent but nevertheless incisional hernia rates were low with no instances of mesh-related bowel erosion or fistulation.

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.

Investigating knowledge regarding antibiotics among pharmacy and allied health sciences students in a Sri Lankan university

INTRODUCTION

Education and adequate training regarding the appropriate use of antibiotics for health care professionals is essential in developing countries. Educational strategies can also influence appropriate antibiotic use in the community. The aim of this study was to assess and compare knowledge of antibiotics and antimicrobial resistance (AMR) between pharmacy and other allied health sciences (AHS) students at the University of Peradeniya, Sri Lanka.

METHODOLOGY

A cross-sectional study was conducted at the University of Peradeniya, Sri Lanka, which offers undergraduate teaching in pharmacy and other AHS; nursing, radiography and medical laboratory sciences. All students in each program were invited to participate in this study. Data was collected using a self-administered questionnaire. Descriptive data analysis and Chi square tests were performed.

RESULTS

Pharmacy (n = 102) and other AHS students (n = 284) completed the questionnaire (response rate 69%). A majority of participants (76%) reported antibiotic use in the past year. A significantly higher proportion of pharmacy students reported antibiotic use was appropriate for the management of skin wound infection, urinary tract infection and sore throat compared to AHS students, p < 0.05. No significant differences were observed between pharmacy and AHS students regarding knowledge of AMR. Most students understood terms related to antibiotic resistance through their undergraduate studies.

CONCLUSION

Pharmacy students demonstrated better knowledge and understanding regarding antibiotics utilization than AHS students. Both pharmacy and AHS students had good understanding regarding AMR. The undergraduate curricula of pharmacy and AHS have contributed significantly to understanding the terminology associated with antibiotics and AMR.

Impact of ovarian metastases on survival in patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignancy originating from appendiceal and colorectal cancer

AIM

Ovarian metastases from gastrointestinal tract malignancies have been considered an ominous finding with poor prognosis. The aim of this project was to determine the impact on survival, and potential cure, when cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are combined to treat peritoneal malignancy in women with Krukenberg tumours.

METHOD

A retrospective analysis of prospectively collected data between January 2010 and July 2015. Female patients undergoing complete CRS (macroscopic tumour removal) and HIPEC for pseudomyxoma peritonei (PMP) of appendiceal origin, or colorectal peritoneal metastases (CPM) were included. Survival was estimated using the Kaplan-Meier method and survival rates compared using the log-rank test.

RESULTS

In total, 889 patients underwent surgery for peritoneal malignancy, of whom 551 were female. Of these, 504/551 (91%) underwent complete CRS and HIPEC. Overall, 405/504 (80%) had at least one involved ovary removed either during CRS and HIPEC or at their index prereferral operation. Three hundred and fifty-two patients (87%) had an appendiceal tumour and 53 (13%) had CPM. At a median follow up of 40 months, overall survival (OS) did not differ significantly between patients with or without ovarian involvement in women with a primary low-grade appendiceal tumour or CPM. In women with high-grade primary appendiceal pathology, OS was significantly lower in patients with ovarian metastases compared with those without ovarian involvement.

CONCLUSION

Women with ovarian metastases from low-grade appendiceal tumours or colorectal cancer treated with CRS and HIPEC have similar survival rates to patients without ovarian metastases. Long-term survival and cure is feasible in patients amenable to complete tumour removal.

Scaling analysis of the viscoelastic response of linear polymers

Viscoelastic response in terms of the complex shear modulus G^*(ω) of the linear polymers poly(ethylene-alt-propylene), poly(isoprene), and poly(butadiene) is studied for molar masses (M) from 3k up to 1000k and over a wide temperature range starting from the glass transition temperature T_g (174 K-373 K). Master curves G'(ωτ_α) and G″(ωτ_α) are constructed for the polymer-specific relaxation. Segmental relaxation occurring close to T_g is independently addressed by single spectra. Altogether, viscoelastic response is effectively studied over 14 decades in frequency. The structural relaxation time τ_α used for scaling is taken from dielectric spectra. We suggest a derivative method for identifying the different power-law regimes and their exponents along G″(ωτ_α) ∝ ω^ε″. The exponent ε″ = ε″(ωτ_α) ≡ d ln G″(ωτ_α)/d ln(ωτ_α) reveals more details compared to conventional analyses and displays high similarity among the polymers. Within a simple scaling model, the original tube-reptation model is extended to include contour length fluctuations (CLFs). The model reproduces all signatures of the quantitative theory by Likhtman and McLeish. The characteristic times and power-law exponents are rediscovered in ε″(ωτ_α). The high-frequency flank of the terminal relaxation closely follows the prediction for CLF (ε″ = -0.25), i.e., G″(ω) ∝ ω^-0.21±0.02. At lower frequencies, a second regime with lower exponent ε″ is observed signaling the crossover to coherent reptation. Application of the full Likhtman-McLeish calculation provides a quantitative interpolation of ε″(ωτ_α) at frequencies below those of the Rouse regime. The derivative method also allows identifying the entanglement time τ_e. However, as the exponent in the Rouse regime (ωτ_e > 1) varies along ε_eRouse = 0.66 ± 0.04 (off the Rouse prediction ε_Rouse = 0.5) and that at ωτ_e < 1 is similar, only a weak manifestation of the crossover at τ_e is found at highest M. Yet, calculating τ_e/τ_α= (M/M_o)², we find good agreement among the polymers when discussing ε″(ωτ_e). The terminal relaxation time τ_t is directly read off from ε″(ωτ_α). Plotting τ_t/τ_e as a function of Z = M/M_e, we find universal behavior as predicted by the TR model. The M dependence crosses over from an exponent significantly larger than 3.0 at intermediate M to an exponent approaching 3.0 at highest M in agreement with previous reports. The frequency of the minimum in G″(ωτ_α) scales as τ_min ∝ M^1.0±0.1. An M-independent frequency marks the crossover to glassy relaxation at the highest frequencies. Independent of the amplitude of G″(ω), which may be related to sample-to-sample differences, the derivative method is a versatile tool to provide a detailed phenomenological analysis of the viscoelastic response of complex liquids.