Elevated procalcitonin is associated with increased mortality in patients with scrub typhus infection needing intensive care admission

Clinical, laboratory profile and molecular characterization of Orientia tsutsugamushi among fatal scrub typhus patients from Karnataka, India

BACKGROUND

Scrub typhus is a vector-borne infection caused by the obligate intracellular organism Orientia tsutsugamushi. In some cases, scrub typhus can result in severe complications, multiorgan failure and death.

OBJECTIVE

To study the clinical and laboratory profiles of patients who succumbed to scrub typhus.

METHODS

A prospective cohort study was conducted from August 2019 through April 2023 on scrub typhus patients admitted to our hospital. Clinical and laboratory parameters of all the patients were recorded, and blood samples were drawn. To confirm scrub typhus, a nested polymerase chain reaction (nPCR) was performed in collected samples. Viable amplicons were sequenced, and phylogenetic analyses were performed to identify infecting genotypes.

RESULTS

A total of 261 patients were enrolled. Of these, nine (3.45%) patients succumbed at a median (Interquartile Range) duration of 5 (1.5, 10.5) days after admission. Sepsis with septic shock (9, 100%) and acute kidney injury (AKI) (6, 66%) were noted among the succumbed patients. All the succumbed patients (100%) required intensive care admission, inotropic and ventilatory support. While 5 (55%) patients required dialysis, two (22%) required blood transfusion. Three (33%) patient samples were co-positive for Leptospira IgM, and four (44%) patients had superinfection with Candida tropicalis, multi-drug-resistant (MDR) E. Coli sepsis, pan drug-resistant (PDR) Acinetobacter Baumanii, and Klebsiella pneumoniae. Phylogenetic analysis revealed Orientia tsutsugamushi Japanese Gilliam-variant (JG-v) like (50%), Karp-like (37.5%), and Japanese Gilliam (JG) like (12.5%) strains among succumbed patients.

CONCLUSION

Delay in scrub typhus diagnosis can result in severe complications, septic shock, and multisystem organ failure, culminating in death.

Human rickettsial infections in India - A review

Rickettsial infections are emerging and/or re-emerging disease that poses a serious global threat to humans and animals. Transmission to humans and animals is through the bite of the ectoparasites including ticks, fleas and chigger mites. Most of the rickettsial diseases are endemic in India, but underdiagnosed. This review is aimed at analyzing the prevalence of rickettsiosis in India and the advancement of rickettsial diagnosis. We have conducted a systematic review on the prevalence of rickettsial disease in India ranging from 1.3% to 46.6% for spotted fever, 2.4% to 77.8% for scrub typhus and 1% to 46.4% for Q fever, based on the literature published with the evidence of isolation, serological, and molecular diagnostics. Search engines Medline/PubMed, Science Direct, ProQuest, and EBSCO were used to retrieve the articles from electronic databases by using appropriate keywords to track the emergence of these rickettsial diseases in India for the period of 1865 to till date. We retrieved 153 published rickettsial articles on hospital-based studies from India that were purely made on the basis of prevalence and the laboratory parameters viz., Weil-Felix test (WF) and Rapid Immunochromatographic tests (RICT) with reference to the gold standard IFA and ELISA. More epidemiological studies are required for epidemic typhus to know the exact prevalence status of this louse-borne rickettsiosis in India. Currently, there is no confirmed specific inflammatory marker for rickettsial diseases. Moreover, serological cross-reactivity is an important aspect, and it should be investigated in endemic areas, there is also a need to include molecular diagnostic techniques for further confirmation in healthcare settings.

Rickettsial Infections Are Neglected Causes of Acute Febrile Illness in Teluk Intan, Peninsular Malaysia

Rickettsial infections are among the leading etiologies of acute febrile illness in Southeast Asia. However, recent data from Malaysia are limited. This prospective study was conducted in Teluk Intan, Peninsular Malaysia, during January to December 2016. We recruited 309 hospitalized adult patients with acute febrile illness. Clinical and biochemistry data were obtained, and patients were stratified into mild and severe infections based on the sepsis-related organ failure (qSOFA) scoring system. Diagnostic assays including blood cultures, real-time PCR, and serology (IFA and MAT) were performed. In this study, pathogens were identified in 214 (69%) patients, of which 199 (93%) patients had a single etiology, and 15 (5%) patients had >1 etiologies. The top three causes of febrile illness requiring hospitalization in this Malaysian study were leptospirosis (68 (32%)), dengue (58 (27%)), and rickettsioses (42 (19%)). Fifty-five (18%) patients presented with severe disease with a qSOFA score of ≥2. Mortality was documented in 38 (12%) patients, with the highest seen in leptospirosis (16 (42%)) followed by rickettsiosis (4 (11%)). While the significance of leptospirosis and dengue are recognized, the impact of rickettsial infections in Peninsular Malaysia remains under appreciated. Management guidelines for in-patient care with acute febrile illness in Peninsular Malaysia are needed.

Procalcitonin (PCT)-guided antibiotic stewardship in Asia-Pacific countries: adaptation based on an expert consensus meeting

Introduction Recently, an expert consensus on optimal use of procalcitonin (PCT)-guided antibiotic stewardship was published focusing mainly on Europe and the United States. However, for Asia-Pacific countries, recommendations may need adaptation due to differences in types of infections, available resources and standard of clinical care. Methods Practical experience with PCT-guided antibiotic stewardship was discussed among experts from different countries, reflecting on the applicability of the proposed Berlin consensus algorithms for Asia-Pacific. Using a Delphi process, the group reached consensus on two PCT algorithms for the critically ill and the non-critically ill patient populations. Results The group agreed that the existing evidence for PCT-guided antibiotic stewardship in patients with acute respiratory infections and sepsis is generally valid also for Asia-Pacific countries, in regard to proposed PCT cut-offs, emphasis on diagnosis, prognosis and antibiotic stewardship, overruling criteria and inevitable adaptations to clinical settings. However, the group noted an insufficient database on patients with tropical diseases currently limiting the clinical utility in these patients. Also, due to lower resource availabilities, biomarker levels may be measured less frequently and only when changes in treatment are highly likely. Conclusions Use of PCT to guide antibiotic stewardship in conjunction with continuous education and regular feedback to all stakeholders has high potential to improve the utilization of antibiotic treatment also in Asia-Pacific countries. However, there is need for adaptations of existing algorithms due to differences in types of infections and routine clinical care. Further research is needed to understand the optimal use of PCT in patients with tropical diseases.

Predictors of Severity of Scrub Typhus in Children Requiring Pediatric Intensive Care Admission

Objective of our study was to determine the clinical characteristics and laboratory profile of scrub typhus patients requiring pediatric intensive care admission and to find out risk factors for the severity of illness. This was a cross-sectional observational study conducted on 1-month to 12-year-old children admitted with scrub typhus in a tertiary care pediatric intensive care unit (PICU). Relevant demographic, clinical, laboratory, treatment, and outcome-related data were documented. The severity of the disease was measured in the form of multiple organ dysfunction syndrome (MODS). With further correlation, and univariate and multivariate analyses, factors associated with severe disease were identified. During the study period, out of 586 PICU admission, 62 patients (10.6%) were diagnosed with scrub typhus. The mean age was 63.85 ± 52.78 months, where infants constituted 32.3% of the total population. Fever was present in 100% of the cases. Common indications of PICU admission were: respiratory distress 42 (67.7%), altered sensorium 41 (66.1%), convulsion 37 (59.7%), and shock 31 (50%). Total number of patients with MODS was 40 (64.5%). The case fatality rate was 8%. On multivariate analysis, infant age group (p = 0.02), altered sensorium (p = 0.001), reduced urine output (p = 0.02), thrombocytopenia (p = 0.001), raised C-reactive protein (p = 0.004), hyponatremia (p = 0.005), hypoalbuminemia (p = 0.01), deranged international normalized ratio (p = 0.02), and hyperferritinemia (p = 0.02) came out to be independent factors in predictability for development of MODS. Multiorgan dysfunction is a life-threatening manifestation of scrub typus in children, which necessitates PICU admission. Infant age group, presence of altered sensorium, reduced urine output, thrombocytopenia, elevated inflammatory markers, coagulopathy, hypoalbuminemia, and hyponatremia predict risk for MODS.

Serum C-reactive protein and procalcitonin values in acute Q fever, scrub typhus, and murine typhus

Background

Although C-reactive protein (CRP) and procalcitonin (PCT) are widely used inflammatory markers for infectious diseases, their role and potential application for rickettsioses were rarely studied.

Methods

A retrospective chart review and serological study were conducted in patients with rickettsioses. The clinical presentations, characteristics, laboratory data, and treatment responses were recorded and their associations with CRP and PCT values were analyzed.

Results

A total of 189 cases of rickettsioses, including 115 cases of acute Q fever (60.8%), 55 cases of scrub typhus (29.1%), and 19 cases of murine typhus (10.1%) were investigated. Both CRP and PCT values increased in the acute phase and declined in the convalescent phase. In the acute phase, mean CRP and PCT values were 78.2 ± 63.7 mg/L and 1.05 ± 1.40 ng/mL, respectively. Percentages of patients falling under different cut-off values of CRP and PCT were calculated systematically. Only 10.8% of CRP was > 150 mg/L and 14.2% of PCT was > 2.0 ng/mL. Patients with delayed responses to doxycycline treatment (> 3 days from treatment to defervescence) had significantly higher CRP values (102.7 ± 77.1 vs. 72.2 ± 58.2 mg/L, p = 0.041) and more PCT > 1.0 ng/ml (48.4% vs. 26.0%, p = 0.019) in the acute phase; higher CRP values (19.1 ± 37.4 vs. 3.6 ± 13.1 mg/L, p = 0.049) and more PCT > 0.5 ng/ml (19.2% vs. 1.4%, p = 0.005) in the convalescent phase. Correlation analysis was conducted for patients with acute Q fever. CRP and PCT values were positively correlated to each other, and both markers also had a positive correlation with serum aspartate transaminase values. Both CRP and PCT values and white blood cell counts were positively correlated to the days needed from doxycycline treatment to defervescence.

Conclusion

CRP and PCT values might be useful in clinical investigations for patients with suspected rickettsioses and in predicting the response to doxycycline treatment for rickettsioses.

Predictors of Mortality in Scrub Typhus Infection Requiring Intensive Care Admission in Tertiary Healthcare Centre of Nepal

Introduction

This study aimed to explore the predictors of mortality from scrub typhus infection in patients requiring intensive care unit (ICU) admission.

Materials and Methods

A retrospective study was conducted on 120 patients with serum ELISA IgM positive for scrub typhus (optical density ≥ 0.5) admitted at the medical ICU of Chitwan Medical College Teaching Hospital between April 2016 and September 2017. Data was extracted from patient medical records and electronic database of the hospital. The outcome measurement was mortality (Yes/No) due to the infection. A multivariate binary logistic regression analysis (p < 0.10) using potential variables from bivariate analysis (p < 0.25) was adjusted to predict the mortality.

Results

The mortality rate was 20% (24/120). Factors associated with mortality, as found using bivariate analysis, were heart rate > 100/minute (p < 0.001), systolic blood pressure < 90 mmHg (p = 0.025), diastolic blood pressure < 60 mmHg (p = 0.032), serum creatinine > 1.4 mg/dl (p < 0.001), acute kidney injury requiring dialysis (p = 0.029), acute respiratory distress syndrome (p < 0.001), and shock requiring vasopressor (p < 0.001). Regression analysis showed age (odds ratio [OR] = 1.063; 95% CI = 1.010-1.118; p = 0.019) and serum creatinine (OR = 1.063; 95% CI = 1.010-1.118; p = 0.019) as significant predictors of poor outcome.

Conclusion

Older age and high serum creatinine were found to be independent predictors of poor outcome in patients with scrub typhus admitted in medical ICU.

Role of Procalcitonin in the Management of Infected Patients in the Intensive Care Unit

The combination of molecular pathogen diagnostics and the biomarker procalcitonin (PCT) are changing the use of antimicrobials in patients admitted to critical care units with severe community-acquired pneumonia, possible septic shock, or other clinical syndromes. An elevated serum PCT level is good supportive evidence of a bacterial pneumonia, whereas a low serum PCT level virtually eliminates an etiologic role for bacteria even if the culture for a potential bacterial pathogen is positive. Serum PCT levels can be increased in any shocklike state; a low PCT level eliminates invasive bacterial infection as an etiology in more than 90% of patients.

Spectrum and outcome of acute infectious encephalitis/encephalopathy in an intensive care unit from India

PURPOSE

To evaluate the spectrum of acute infectious encephalitis/encephalopathy syndrome (AIES) in intensive care unit (ICU) and the predictors of mechanical ventilation (MV) and outcome of these patients.

METHODS

AIES patients diagnosed on the basis of fever, altered sensorium, seizure and cerebrospinal fluid pleocytosis admitted to the neurology ICU were prospectively included. The demographic and clinical details, hematological, biochemical, MRI and etiological findings of the patients were noted. Need of MV, death in hospital and 3-month functional outcome were analyzed.

RESULTS

One hundred sixty-four out of 258 (64%) AIES patients needed ICU admission. Their median age was 35 (2-85) years and 71 (43%) were females. The etiology was viral in 44 (herpes and Japanese encephalitis in 12 each, dengue in 17, mumps, measles and varicella in 1 patient each), non-viral in 64 (scrub typhus in 48, falciparum malaria in 6, leptospira in 3 and bacterial in 7) and undetermined etiology in 56 (34%) patients. Sixty-nine (42%) patients needed MV. On multivariate analysis, Glasgow Coma Scale (GCS) score, Sequential Organ Failure Assessment (SOFA) score and raised intracranial pressure were independent predictors of MV. Forty-three (26%) patients died, and all were in the MV group. Higher SOFA score and untreatable etiology were independent predictors of mortality. At 3-month follow-up, 14% had poor and 86% had good outcome. Low GCS score, focal weakness and status epilepticus independently predicted poor outcome.

CONCLUSION

Twenty-six percent patients with AIES died in ICU, and 86% had good recovery at 3 months. Admission SOFA scores and untreatable etiology predicted mortality.

Severe scrub typhus infection: Clinical features, diagnostic challenges and management

Scrub typhus infection is an important cause of acute undifferentiated fever in South East Asia. The clinical picture is characterized by sudden onset fever with chills and non-specific symptoms that include headache, myalgia, sweating and vomiting. The presence of an eschar, in about half the patients with proven scrub typhus infection and usually seen in the axilla, groin or inguinal region, is characteristic of scrub typhus. Common laboratory findings are elevated liver transaminases, thrombocytopenia and leukocytosis. About a third of patients admitted to hospital with scrub typhus infection have evidence of organ dysfunction that may include respiratory failure, circulatory shock, mild renal or hepatic dysfunction, central nervous system involvement or hematological abnormalities. Since the symptoms and signs are non-specific and resemble other tropical infections like malaria, enteric fever, dengue or leptospirosis, appropriate laboratory tests are necessary to confirm diagnosis. Serological assays are the mainstay of diagnosis as they are easy to perform; the reference test is the indirect immunofluorescence assay (IFA) for the detection of IgM antibodies. However in clinical practice, the enzyme-linked immuno-sorbent assay is done due to the ease of performing this test and a good sensitivity and sensitivity when compared with the IFA. Paired samples, obtained at least two weeks apart, demonstrating a ≥ 4 fold rise in titre, is necessary for confirmation of serologic diagnosis. The mainstay of treatment is the tetracycline group of antibiotics or chloramphenicol although macrolides are used alternatively. In mild cases, recovery is complete. In severe cases with multi-organ failure, mortality may be as high as 24%.

Biomarkers for sepsis: a review with special attention to India

Sepsis is a serious infection and still a common cause of morbidity and mortality in resource-limited settings such as India. Even when microbiologic diagnostics are available, bacteremia is only identified in a proportion of patients who present with sepsis and bloodstream infections. Biomarkers have been used in a variety of disease processes and can help aid in diagnosing bacterial infections. There have been numerous biomarkers investigated to aid with diagnosis and prognostication in sepsis with the majority suffering from lack of sensitivity or specificity. Procalcitonin has been heralded as the biomarker that holds the most promise for bloodstream infections. Data are emerging in India, and in this review, we focus on the current data of biomarkers in sepsis with particular attention to how biomarkers could be used to augment diagnosis and treatment in India.