Clinical Profile and Predictors of Intensive Care Unit Admission in Pediatric Scrub Typhus: A Retrospective Observational Study from North India

Epidemiology of scrub typhus and other rickettsial infections (2018-22) in the hyper-endemic setting of Mizoram, North-East India

BACKGROUND

In the past decade, scrub typhus cases have been reported across India, even in regions that had no previous history of the disease. In the North-East Indian state of Mizoram, scrub typhus cases were first recorded only in 2012. However, in the last five years, the state has seen a substantial increase in the scrub typhus and other rickettsial infections. As part of the public health response, the Mizoram Government has integrated screening and line listing of scrub typhus and other rickettsial infections across all its health settings, a first in India. Here we detail the epidemiology of scrub typhus and other rickettsial infections from 2018-2022, systematically recorded across the state of Mizoram.

METHODOLOGY/PRINCIPAL FINDINGS

The line-listed data positive for scrub typhus and other rickettsial infections identified by rapid immunochromatographic test and/or Weil-Felix test from 2018-22 was used for the analysis. During this period, 22,914 cases of rickettsial infections were recorded, out of which 19,651 were scrub typhus cases. Aizawl is the worst affected, with 10,580 cases (46.17%). The average incidence of rickettsial infections is 3.54 cases per 1000 persons-year, and the case fatality rate is 0.35. Only ∼2% of the reported scrub typhus cases had eschar. Multivariate logistic regression analysis indicate patients with eschar (aOR = 2.5, p<0.05), occupational workers [farmers (aOR:3.9), businessmen (aOR:1.8), construction workers (aOR:17.9); p<0.05], and children (≤10 years) (aOR = 5.4, p<0.05) have higher odds of death due to rickettsial infections.

CONCLUSION

The integration of systematic surveillance and recording of rickettsial diseases across Mizoram has shed important insights into their prevalence, morbidity, and mortality. This study underscores the importance of active surveillance of rickettsial infections across India, as the burden could be substantially higher, and is probably going undetected.

Haemodynamic support for paediatric septic shock: a global perspective

Septic shock is a leading cause of hospitalisation, morbidity, and mortality for children worldwide. In 2020, the paediatric Surviving Sepsis Campaign (SSC) issued evidence-based recommendations for clinicians caring for children with septic shock and sepsis-associated organ dysfunction based on the evidence available at the time. There are now more trials from multiple settings, including low-income and middle-income countries (LMICs), addressing optimal fluid choice and amount, selection and timing of vasoactive infusions, and optimal monitoring and therapeutic endpoints. In response to developments in adult critical care to trial personalised haemodynamic management algorithms, it is timely to critically reassess the current state of applying SSC guidelines in LMIC settings. In this Viewpoint, we briefly outline the challenges to improve sepsis care in LMICs and then discuss three key concepts that are relevant to management of children with septic shock around the world, especially in LMICs. These concepts include uncertainties surrounding the early recognition of paediatric septic shock, choices for initial haemodynamic support, and titration of ongoing resuscitation to therapeutic endpoints. Specifically, given the evolving understanding of clinical phenotypes, we focus on the controversies surrounding the concepts of early fluid resuscitation and vasoactive agent use, including insights gained from experience in LMICs and high-income countries. We outline the key components of sepsis management that are both globally relevant and translatable to low-resource settings, with a view to open the conversation to the large variety of treatment pathways, especially in LMICs. We emphasise the role of simple and easily available monitoring tools to apply the SSC guidelines and to tailor individualised support to the patient's cardiovascular physiology.

Clinical profile and outcomes of pediatric scrub typhus associated with elevated hepatic transaminases

BACKGROUND

Hepatic transaminase (HT) elevation is frequently seen in children with scrub typhus (ST), but the clinical implication of this common finding is not known.

OBJECTIVE

To describe the clinical profile and outcome of pediatric ST with elevated hepatic transaminase.

METHODS

In this prospective cohort study, all children < 12 years of age presenting with fever for ≥ 5 days and positive immunoglobulin M (IgM) serology for ST were included. Clinical findings, laboratory features and outcomes of children with elevated HT were compared with those who had normal HT.

RESULTS

Of 560 ST positive children included, 257 (45.8%) had associated HT elevation. The common age group affected was 5 to 12 years of age (54.9%). Most of the children came during the second week of fever (68.5%) with mean duration of fever of 9.1 days. The common initial presenting symptoms were cough (77.8%), vomiting (65%) and myalgia (59.1%) and signs were hepatomegaly (64.2%), splenomegaly (57.6%) and generalized lymphadenopathy (54.1%). Eschar was seen in 49.8% of children. Thrombocytopenia (58%) and anemia (49%) were the frequently seen laboratory abnormalities. Severe forms of ST were seen in 45.5% children, of which pneumonia was most common. The fever clearance time (48 ± 19.2 h) and mean duration of hospital stay (6.7 ± 3.3 days) were prolonged in these children. On logistic regression analysis, generalized lymphadenopathy (p = 0.002), ascites (p = 0.037), thrombocytopenia (p < 0.001) and hypoalbuminemia (p = 0.023) were found to be associated with HT elevation in these children.

CONCLUSIONS

Hepatic transaminase (HT) levels increase with the duration of untreated fever and is found to be associated with severe forms of scrub typhus. Children with elevated HT have delay in fever defervescence and their duration of hospital stay was prolonged.

Scrub typhus, a salient threat: Needs attention

Scrub typhus (ST) infection is one of the most significant causes of acute undifferentiated febrile illness, and its prevalence has been increasing across the globe. Clinical suspicion and growing clinical understanding among healthcare professionals have resulted in the rapid diagnosis and effective management. Since ST has the potential to cause multiorgan failure and a higher mortality rate, it is critical to enhance surveillance, make rapid diagnosis, and administer antibiotics appropriately.

Diagnostic, Management, and Research Considerations for Pediatric Acute Respiratory Distress Syndrome in Resource-Limited Settings: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

Diagnosis of pediatric acute respiratory distress syndrome (PARDS) in resource-limited settings (RLS) is challenging and remains poorly described. We conducted a review of the literature to optimize recognition of PARDS in RLS and to provide recommendations/statements for clinical practice and future research in these settings as part of the Second Pediatric Acute Lung Injury Consensus Conference (PALICC-2).

DATA SOURCES

MEDLINE (Ovid), Embase (Elsevier), and CINAHL Complete (EBSCOhost).

STUDY SELECTION

We included studies related to precipitating factors for PARDS, mechanical ventilation (MV), pulmonary and nonpulmonary ancillary treatments, and long-term outcomes in children who survive PARDS in RLS.

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize evidence and develop recommendations. Seventy-seven studies were identified for full-text extraction. We were unable to identify any literature on which to base recommendations. We gained consensus on six clinical statements (good practice, definition, and policy) and five research statements. Clinicians should be aware of diseases and comorbidities, uncommon in most high-income settings, that predispose to the development of PARDS in RLS. Because of difficulties in recognizing PARDS and to avoid underdiagnosis, the PALICC-2 possible PARDS definition allows exclusion of imaging criteria when all other criteria are met, including noninvasive metrics of hypoxemia. The availability of MV support, regular MV training and education, as well as accessibility and costs of pulmonary and nonpulmonary ancillary therapies are other concerns related to management of PARDS in RLS. Data on long-term outcomes and feasibility of follow-up in PARDS survivors from RLS are also lacking.

CONCLUSIONS

To date, PARDS remains poorly described in RLS. Clinicians working in these settings should be aware of common precipitating factors for PARDS in their patients. Future studies utilizing the PALICC-2 definitions are urgently needed to describe the epidemiology, management, and outcomes of PARDS in RLS.

Pathobiology, Severity, and Risk Stratification of Pediatric Acute Respiratory Distress Syndrome: From the Second Pediatric Acute Lung Injury Consensus Conference

OBJECTIVES

To review the literature for studies published in children on the pathobiology, severity, and risk stratification of pediatric acute respiratory distress syndrome (PARDS) with the intent of guiding current medical practice and identifying important areas for future research related to severity and risk stratification.

DATA SOURCES

Electronic searches of PubMed and Embase were conducted from 2013 to March 2022 by using a combination of medical subject heading terms and text words to capture the pathobiology, severity, and comorbidities of PARDS.

STUDY SELECTION

We included studies of critically ill patients with PARDS that related to the severity and risk stratification of PARDS using characteristics other than the oxygenation defect. Studies using animal models, adult only, and studies with 10 or fewer children were excluded from our review.

DATA EXTRACTION

Title/abstract review, full-text review, and data extraction using a standardized data collection form.

DATA SYNTHESIS

The Grading of Recommendations Assessment, Development, and Evaluation approach was used to identify and summarize relevant evidence and develop recommendations for clinical practice. There were 192 studies identified for full-text extraction to address the relevant Patient/Intervention/Comparator/Outcome questions. One clinical recommendation was generated related to the use of dead space fraction for risk stratification. In addition, six research statements were generated about the impact of age on acute respiratory distress syndrome pathobiology and outcomes, addressing PARDS heterogeneity using biomarkers to identify subphenotypes and endotypes, and use of standardized ventilator, physiologic, and nonpulmonary organ failure measurements for future research.

CONCLUSIONS

Based on an extensive literature review, we propose clinical management and research recommendations related to characterization and risk stratification of PARDS severity.

Pediatric Scrub Typhus Manifesting with Multisystem Inflammatory Syndrome: A New Cause for Confusion or Concern—A Case Series

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has discovered a new disease called multisystem inflammatory syndrome in children (MIS-C). In developing nations, pediatricians must be mindful of the similarities between MIS-C and other tropical fevers such as scrub typhus. Not only should such patients be kept on high alert to rule out tropical diseases and receive appropriate treatment, such as steroids or immunomodulatory medications, but this is also concerning because, if rickettsial or bacterial infection is not detected through cultures and serology, steroid, or immunomodulatory treatment alone can be fatal.

How to cite this article: Bhardwaj P, Sood M, Singh R. Pediatric Scrub Typhus Manifesting with Multisystem Inflammatory Syndrome: A New Cause for Confusion or Concern—A Case Series. Indian J Crit Care Med 2022;26(6):723–727.

Clinical characteristics and risk factors for severe scrub typhus in pediatric and elderly patients

Background

Scrub typhus (ST) is a life-threatening infectious disease if appropriate treatment is unavailable. Large discrepancy of clinical severity of ST patients was reported among age groups, and the underlying risk factors for severe disease are unclear.

Methods

Clinical and epidemiological data of ST patients were collected in 55 surveillance hospitals located in Guangzhou City, China, from 2012 to 2018. Severe prognosis and related factors were determined and compared between pediatric and elderly patients.

Results

A total of 2,074 ST patients including 209 pediatric patients and 1,865 elderly patients were included, with a comparable disease severity rate of 11.0% (95% CI 7.1%–16.1%) and 10.3% (95% CI 9.0%–11.8%). Different frequencies of clinical characteristics including lymphadenopathy, skin rash, enlarged tonsils, etc. were observed between pediatric and elderly patients. Presence of peripheral edema and decreased hemoglobin were the most important predictors of severe illness in pediatric patients with adjusted ORs by 38.99 (9.96–152.67, p<0.001) and 13.22 (1.54–113.50, p = 0.019), respectively, while presence of dyspnea and increased total bilirubin were the potential determinants of severe disease in elderly patients with adjusted ORs by 11.69 (7.33–18.64, p<0.001) and 3.17 (1.97–5.11, p<0.001), respectively. Compared with pediatric patients, elderly patients were more likely to receive doxycycline (64.8% v.s 9.9%, p<0.001), while less likely to receive azithromycin therapy (5.0% v.s 41.1%, p<0.001).

Conclusion

The disease severity rate is comparable between pediatric and elderly ST patients, while different clinical features and laboratory indicators were associated with development of severe complications for pediatric and elderly patients, which is helpful for diagnosis and progress assessment of disease for ST patients.

The study investigated different clinical features and risk factors for severe disease between pediatric and elderly patients with scrub typhus. We found that significantly higher frequencies of lymphadenopathy, skin rash, enlarged tonsils, etc. were observed in pediatric patients than elderly patients. Other non-specific signs, subjective complaints, and chest radiographic abnormality were overpresented in elderly patients. Risk factors for severe disease between pediatric and elderly patients with scrub typhus were different. Presence of peripheral edema and decreased hemoglobin were the most important factors for pediatric patients, while presence of dyspnea and increased total bilirubin for elderly patients. These findings reminded medical workers to acknowledge this important difference and to adopt an age specific method in the differential diagnosis and risk assessment for scrub typhus.

Profile of Scrub Typhus Meningitis/Meningoencephalitis in Children with and without Scrub Typhus IgM Antibody in CSF

The aim of this article was to study the spectrum of scrub typhus meningitis/meningoencephalitis (STM) cases in children. Children ≤14 years of age with acute undifferentiated febrile illness were included. Immunoglobulin M (IgM) enzyme-linked immunosorbent assay was done in blood and cerebrospinal fluid (CSF) of children with suspected STM. Demographic, clinical, and laboratory details were expressed as descriptive statistics. Factors associated with neurological involvement were identified on univariate analysis. A total of 76 children had ST during the study period (meningitis/meningoencephalitis = 8 [10.5%], of which 5 [62.5%] had detectable ST IgM antibodies in CSF). The included children were 4 to 12 years of age with boys > girls. Headache and vomiting were common in those with STM, whereas hyponatremia and thrombocytopenia were common in those without STM. All children with STM recovered with sequelae in one child (right lateral rectus palsy). There was no mortality. STM has an incidence of 10.5% in children with ST from Eastern India. Headache and vomiting were significant predictors of STM, whereas hyponatremia and thrombocytopenia were significant predictor of non-STM.

Mortality and complications of scrub typhus in the paediatric population: a systematic review and meta-analysis

Scrub typhus is a leading cause of treatable febrile illness. It can produce complications and dysfunction of multiple organs in children and is associated with considerable mortality. We attempted to perform a systematic review of original articles published between 1990 to 2020 based on certain selection criteria to estimate the case fatality risk of this disease in children. We addressed the pattern of complications of this disease with its impact on mortality We calculated pooled prevalence with a random effects model (restricted maximum likelihood method) that assumed varying effect sizes between studies using R statistical software. We reported the case fatality rate and its 95% confidence intervals (CIs) in the pooled analysis. Thirty-seven articles with a total of 3329 children were identified for inclusion. The case fatality rate was 1.1% (CI 0.05 to 2, I2=58% and prediction interval 0-6%). The mortality rate showed a declining trend over the last 5 y. Hepatitis (30.68% [95% CI 18.52 to 44.38]) remains the most common complication, followed by shock (14.45% [95% CI 7.71 to 22.85]), pneumonia (14.71% [95% CI 9.76 to 20.48]), acute kidney injury (13.72% [95% CI 8.49 to 19.97]) and meningitis/meningoencephalitis (11.57% [95% CI 7.83 to 15.92]). Multi-organ dysfunction syndrome was the main contributor to mortality.

Small joint polyarthritis - An unusual presentation of scrub typhus in a child

Scrub typhus is a common Rickettsial infection which is endemic in tropical regions. It is characterised by fever, eschar, thrombocytopenia, lymphadenopathy and organomegaly. Scrub typhus has significant morbidity and mortality owing to its multisystemic involvement. Non-inflammatory polyarthritis of small joints is an uncommon presentation in paediatric scrub typhus. We discuss a five-year-old boy who presented with fever, small joint polyarthritis, hepatosplenomegaly and pathognomonic eschar with positive scrub IgM ELISA. Arthritis resolved completely with doxycycline therapy without any deformity.

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.

Hyperferritinemia in children hospitalized with scrub typhus

BACKGROUND

Hyperferritinemia is increasingly associated with mortality in sepsis. Studies estimating the prevalence of hyperferritinemia in pediatric scrub typhus are limited.

METHODS

This was a secondary analysis of a prospective observational study (FERRIS) from a tertiary care teaching hospital in North India where 72 children with confirmed scrub typhus, 4 (5.5%) PCR positive, 55 (76.4%)-IgM ELISA positive, and 13 (18.1%)-both PCR and ELISA positive, were analyzed. Serum ferritin was measured in 62 children to identify the prevalence of hyperferritinemia and determine its association with mortality.

RESULTS

Hyperferritinemia (> 500 μg/L) was seen in 72.6% [n = 45] children; 26 (41.9%) were mild (500-2000 μg/L), 13 (21%) were moderate (2000-10,000 μg/L), and 6 (9.7%) were severe (> 10,000 μg/L). Early presentation to hospital (≤ 7 days of febrile illness) had more survivors than late presentation (> 7 days). Non-survivors had significantly higher PRISM III, PELOD-2, hyperlactatemia, hypoalbuminemia, organ dysfunction, need for mechanical ventilation, and need of RRT. Ferritin had poor sensitivity and specificity in predicting survival with AUC of 0.56. Organ dysfunction and risk scores as PRISM III, PELOD 2, and VIS at admission were better predictors with AUC (95% CI) of 0.72 (0.56, 0.89), 0.77 (0.63, 0.92), and 0.90 (0.78, 1.0) respectively.

CONCLUSIONS

Hyperferritinemia is common in scrub typhus but it did not predict survival. Organ dysfunction and risk scores were better predictors of mortality than ferritin.

Pediatric Scrub Typhus: A Commentary

The commentary is to highlight not the profile of scrub typhus but the correlation of serology with immunofluorescence. How to cite this article: Udani S. Pediatric Scrub Typhus: A Commentary. Indian J Crit Care Med 2020;24(6):380.

Serum Ferritin Predicts Neither Organ Dysfunction Nor Mortality in Pediatric Sepsis Due to Tropical Infections

Objective: To evaluate serial ferritin levels measured in the initial 72 h of admission as a biomarker for new and progressive multi organ dysfunction syndrome (NPMODS) and mortality (unfavorable outcomes) in critically ill children with sepsis due to tropical infections. Material and Methods: In this prospective observational study from a tertiary care teaching hospital in India, children 3 month to 12 years with a diagnosis of acute febrile illness and any two features suggesting tropical infections [cytopenia (platelet count <1,00,000/cu.mm, total leucocyte count <4,000/cu.mm), hepatomegaly and/or splenomegaly, lymphadenopathy, systemic signs (rash, edema), respiratory distress, and encephalopathy not accounted by localized infection] were eligible for inclusion. Children with known or suspected disorder of iron metabolism were excluded. Primary outcome was to determine the association of serial ferritin levels with mortality and NPMODS. Secondary outcomes included estimation of the prevalence of hyperferritinemia and comparison of risk prediction scores with serial ferritin measurement in predicting unfavorable outcomes. Measurements and Main Results: In the 202 children enrolled, diagnosis could be established in 133 (65.8%) children. Scrub typhus and dengue were the most common infections. Median (IQR) ferritin measured at admission (n = 183) and on day 3 (n = 120) of hospital stay were 798 (378, 3,205) μg/L and 429 (213,680) μg/L, respectively. Majority (n = 180, 89.1%) had MODS at admission defined as per International pediatric sepsis consensus conference. NPMODS occurred in 47 (23.3%) children of whom 37 (18.3%) died. Children with three or less organ dysfunctions had lower mortality. Neither admission ferritin values nor the percentage change over 72 h was different between children with favorable and unfavorable outcomes. Pediatric Risk of Mortality (PRISM-III) and daily Pediatric Logistic Organ Dysfunction score (dPELOD2 score) were significantly different in those with unfavorable outcomes. Admission ferritin levels and percentage change in 72 h had poor discriminatory power for mortality with AUC of 0.53 (0.53, 0.67) and 0.50 (0.50, 0.64), respectively. dPELOD2 had the best discriminatory power for mortality with AUC of 0.89 (0.89, 0.95). Conclusions: Serial ferritin estimation predicted neither organ dysfunction nor mortality in pediatric sepsis with tropical infections. dPELOD-2 and PRISM-III predicted unfavorable outcomes better than ferritin. The current diagnostic criteria for MODS overestimated organ dysfunctions in tropical infections and hence may need modification with further validation in this epidemiological cohort.