Fever in the tropics: aetiology and case-fatality - a prospective observational study in a tertiary care hospital in South India

Etiological spectrum and diagnostic challenges of short-duration fever in West Bengal (India). A cross-sectional tertiary care study

INTRODUCTION

The scarcity of epidemiological data on acute febrile illnesses from South Asia impairs evidence-based clinical decision-making. Our study aimed to explore the etiological spectrum of short-duration fever in patients admitted to a tertiary care hospital in West Bengal, India.

METHODS

We conducted a cross-sectional study from May 2021 to April 2022 involving 150 adult patients presenting with a fever lasting less than two weeks at Burdwan Medical College and Hospital (West Bengal, India). We performed comprehensive clinical assessments, including microbiological, serological, and other specific investigations, to identify the causes of the fever.

RESULTS

The demographic profile predominantly included individuals aged 21-40 years, with a male-to-female ratio of 1.9:1; 60.7% of participants were from rural areas. The primary etiological agents identified were scrub typhus (25.3%), dengue (15.3%), and enteric fever (13.3%). Notably, 80% of patients presented with non-localizing symptoms, while 14.7% had respiratory symptoms. Blood cultures pinpointed Salmonella typhi and Staphylococcus aureus in a minority of cases (3.3%); malaria, primarily Plasmodium vivax, was diagnosed in 12% of the cases.

CONCLUSION

Our findings highlight the complexity of diagnosing short-duration fevers, dominated by a wide range of etiological agents, with a notable prevalence of scrub typhus. These results underscore the urgent need for enhanced diagnostic facilities, including the availability of scrub typhus testing at primary healthcare centers. We recommend empirical doxycycline therapy for suspected cases and emphasize the need for further research to develop management guidelines for acute febrile illnesses. This study also highlights the importance of raising both community and clinician awareness to prevent irrational antibiotic use.

Diagnostic tools used in the evaluation of acute febrile illness in South India: a scoping review

BACKGROUND

Acute febrile illness (AFI) is characterized by malaise, myalgia and a raised temperature that is a nonspecific manifestation of infectious diseases in the tropics. The lack of appropriate diagnostics for the evaluation of AFI leads to increased morbidity and mortality in resource-limited settings, specifically low-income countries like India. The review aimed to identify the number, type and quality of diagnostics used for AFI evaluation during passive case detection at health care centres in South India.

METHODS

A scoping review of peer-reviewed English language original research articles published between 1946-July 2018 from four databases was undertaken to assess the type and number of diagnostics used in AFI evaluation in South India. Results were stratified according to types of pathogen-specific tests used in AFI management.

RESULTS

The review included a total of 40 studies, all conducted in tertiary care centres (80% in private settings). The studies demonstrated the use of 5-22 tests per patient for the evaluation of AFI. Among 25 studies evaluating possible causes of AFI, 96% tested for malaria followed by 80% for dengue, 72% for scrub typhus, 68% for typhoid and 60% for leptospirosis identifying these as commonly suspected causes of AFI. 54% studies diagnosed malaria with smear microscopy while others diagnosed dengue, scrub typhus, typhoid and leptospirosis using antibody or antigen detection assays. 39% studies used the Weil-Felix test (WFT) for scrub typhus diagnosis and 82% studies used the Widal test for diagnosing typhoid.

CONCLUSIONS

The review demonstrated the use of five or more pathogen-specific tests in evaluating AFI as well as described the widespread use of suboptimal tests like the WFT and Widal in fever evaluation. It identified the need for the development of better-quality tests for aetiological diagnosis and improved standardised testing guidelines for AFI.

Clinical spectrum and outcome of critically ill hospitalized patients with acute febrile illness and new-onset organ dysfunction presenting during monsoon season

Acute febrile illness (AFI) is one of the commonest indications for hospitalization and can present with varying severity including single or multiple organ dysfunction syndrome (MODS). During monsoon season, there is a spurt of AFI often caused by vector borne diseases leading to substantial morbidity and mortality. Our aim was to determine distribution of etiological causes, differential organ involvement and predictors of mortality in critically ill patients with AFI. It was a hospital based observational study which included patients with AFI with dysfunction of at least one organ system. The study was conducted over 4 months during monsoon season. Admitted patients were included who had been subjected to a standard battery of tests and managed with standard hospital based management protocol. 145 patients were included and etiology of fever was ascertained in 81.4% of patients with the most common single infection being chikungunya (20.7%) followed by dengue (20%) fever. Thrombocytopenia and deranged liver biochemistry each were seen in nearly 75% of the patients. Renal (50.3%) and nervous system (46.2%) dysfunction were the predominant organ failures. 49 patients died (33.8%) which correlated with predicted mortality by APACHE (acute physiological assessment and chronic health evaluation) II score. Independent predictors for mortality were older age (> 55 years) (p = 0.01), acidemia (p = 0.01), altered sensorium (p = 0.02) and coagulopathy (p = 0.048). Sub-group analysis revealed that amongst patients with MODS, hypotension could help differentiate between bacterial and non-bacterial causes (p = 0.01). Critically ill patients with AFI suffer from significant morbidity and mortality. Features like the presence of hypotension in MODS may differentiate between a bacterial cause vis-à-vis viral or protozoal etiology.

Non-Respiratory and Non-Diarrheal Causes of Acute Febrile Illnesses in Children Requiring Hospitalization in a Tertiary Care Hospital in North India: A Prospective Study

Acute febrile illnesses (AFIs) in children from the developing world can have varying etiologies. Awareness of local epidemiology helps in prioritizing investigations and empiric treatment. This prospective study was carried out in a tertiary care center in North India, aiming to determine the burden, etiology, and outcome of AFI other than pneumonia and diarrhea in hospitalized children. A total of 613 consecutive children aged 3 months to 12 years with febrile illness of < 7 days during four selected months of 2014 representing different seasons were screened for eligibility. Those with acute respiratory diseases (N = 175, 28.5%) and diarrheal illness (N = 46, 7.5%) were excluded and 217 children were enrolled. Mean (standard deviation) age was 4.8 (3.4) years. Nearly half (N = 91, 41.9%) presented in post-monsoon season. Diagnosis could be established in 187 (86.2%) children. Acute central nervous system infections were the most common (N = 54, 24.8%). Among specific infections, scrub typhus was the most frequent (N = 23, 10.5%) followed by malaria (N = 14, 6.4%), typhoid (N = 14, 6.5%), and viral hepatitis (N = 13, 6.0%). Blood culture had a low (6.5%) yield; Salmonella typhi (N = 6) and Staphylococcus aureus (N = 5) were the common isolates. Serological tests were helpful in 50 (23%) cases. In multivariate analysis, hepatomegaly and/or splenomegaly independently predicted scrub typhus. Mortality rate was 10.1%. We conclude that AFI other than pneumonia and diarrhea are a significant burden and follow a seasonal trend. Scrub typhus has emerged as an important etiology of childhood AFIs in northern India. Periodic review of regional epidemiology will help in understanding the changing pattern of infectious diseases.

Vector-Borne Disease is a Common Cause of Hospitalized Febrile Illness in India

Acute febrile illness (AFI) is a major cause of morbidity and mortality in India and other resource-limited settings, yet systematic etiologic characterization of AFI has been limited. We prospectively enrolled adults (N = 970) and children (age 6 months to 12 years, N = 755) admitted with fever from the community to Sassoon General Hospital in Pune, India, from July 2013 to December 2015. We systematically obtained a standardized clinical history, basic laboratory testing, and microbiologic diagnostics on enrolled participants. Results from additional testing ordered by treating clinicians were also recorded. A microbiological diagnosis was found in 549 (32%) participants; 211 (12%) met standardized case definitions for pneumonia and meningitis without an identified organism; 559 (32%) were assigned a clinical diagnosis in the absence of a confirmed diagnosis; and 406 (24%) had no diagnosis. Vector-borne diseases were the most common cause of AFI in adults including dengue (N = 188, 19%), malaria (N = 74, 8%), chikungunya (N = 15, 2%), and concurrent mosquito-borne infections (N = 23, 2%) occurring most frequently in the 3 months after the monsoon. In children, pneumonia was the most common cause of AFI (N = 214, 28%) and death. Bacteremia was found in 68 (4%) participants. Central nervous system infections occurred in 58 (6%) adults and 64 (8%) children. Etiology of AFI in India is diverse, highly seasonal, and difficult to differentiate on clinical grounds alone. Diagnostic strategies adapted for season and age may reduce diagnostic uncertainty and identify causative organisms in treatable, fatal causes of AFI.

Multiple simultaneous infections in a patient with well-controlled HIV: when Occam's razor fails

Multiple concurrent infectious processes have previously been reported in the context of advanced HIV with significant immunosuppression. Here we report a case of multiple infections in a 56-year-old man with well-controlled HIV diagnosed 5 years earlier. Soon after returning to Australia following 12 years living in Thailand, he became unwell with fevers, night sweats, arthralgia and myalgia. There were no localising symptoms and examination was unremarkable. Investigations revealed positive syphilis (Treponema pallidum) serology with an RPR of 16, a positive urine culture (Klebsiella pneumoniae), a pulmonary nodule, a liver abscess and colitis (Entamoeba histolytica). Recovery was only complete when all the individual infections were treated.

A Predictive Model to Classify Undifferentiated Fever Cases Based on Twenty-Four-Hour Continuous Tympanic Temperature Recording

Diagnosis of undifferentiated fever is a major challenging task to the physician which often remains undiagnosed and delays the treatment. The aim of the study was to record and analyze a 24-hour continuous tympanic temperature and evaluate its utility in the diagnosis of undifferentiated fevers. This was an observational study conducted in the Kasturba Medical College and Hospitals, Mangaluru, India. A total of ninety-six (n = 96) patients were presented with undifferentiated fever. Their tympanic temperature was recorded continuously for 24 hours. Temperature data were preprocessed and various signal characteristic features were extracted and trained in classification machine learning algorithms using MATLAB software. The quadratic support vector machine algorithm yielded an overall accuracy of 71.9% in differentiating the fevers into four major categories, namely, tuberculosis, intracellular bacterial infections, dengue fever, and noninfectious diseases. The area under ROC curve for tuberculosis, intracellular bacterial infections, dengue fever, and noninfectious diseases was found to be 0.961, 0.801, 0.815, and 0.818, respectively. Good agreement was observed [kappa = 0.618 (p < 0.001, 95% CI (0.498–0.737))] between the actual diagnosis of cases and the quadratic support vector machine learning algorithm. The 24-hour continuous tympanic temperature recording with supervised machine learning algorithm appears to be a promising noninvasive and reliable diagnostic tool.

Consensus Guidelines on Evaluation and Management of the Febrile Child Presenting to the Emergency Department in India

JUSTIFICATION

India, home to almost 1.5 billion people, is in need of a country-specific, evidence-based, consensus approach for the emergency department (ED) evaluation and management of the febrile child.

PROCESS

We held two consensus meetings, performed an exhaustive literature review, and held ongoing web-based discussions to arrive at a formal consensus on the proposed evaluation and management algorithm. The first meeting was held in Delhi in October 2015, under the auspices of Pediatric Emergency Medicine (PEM) Section of Academic College of Emergency Experts in India (ACEE-INDIA); and the second meeting was conducted at Pune during Emergency Medical Pediatrics and Recent Trends (EMPART 2016) in March 2016. The second meeting was followed with futher e-mail-based discussions to arrive at a formal consensus on the proposed algorithm.

OBJECTIVE

To develop an algorithmic approach for the evaluation and management of the febrile child that can be easily applied in the context of emergency care and modified based on local epidemiology and practice standards.

RECOMMENDATIONS

We created an algorithm that can assist the clinician in the evaluation and management of the febrile child presenting to the ED, contextualized to health care in India. This guideline includes the following key components: triage and the timely assessment; evaluation; and patient disposition from the ED. We urge the development and creation of a robust data repository of minimal standard data elements. This would provide a systematic measurement of the care processes and patient outcomes, and a better understanding of various etiologies of febrile illnesses in India; both of which can be used to further modify the proposed approach and algorithm.

Tropical Fevers in Indian Intensive Care Units: A Prospective Multicenter Study

Background and Aims

Infections in tropics often present as undifferentiated fevers with organ failures. We conducted this nationwide study to identify the prevalence, profile, resource utilization, and outcome of tropical fevers in Indian Intensive Care Units (ICUs).

Materials and Methods

This was a multicenter prospective observational study done in 34 ICUs across India (July 2013-September 2014). Critically ill adults and children with nonlocalizing fever >48 h and onset < 14 days with any of the following: thrombocytopenia/rash, respiratory distress, renal failure, encephalopathy, jaundice, or multiorgan failure were enrolled consecutively.

Results

Of 456 cases enrolled, 173 were children <12 years. More than half of the participants (58.7%) presented in postmonsoon months (August-October). Thrombocytopenia/rash was the most common presentation (60%) followed by respiratory distress (46%), encephalopathy (28.5%), renal failure (23.5%), jaundice (20%), and multiorgan failure (19%). An etiology could be established in 365 (80.5%) cases. Dengue (n = 105.23%) was the most common followed by scrub typhus (n = 83.18%), encephalitis/meningitis (n = 44.9.6%), malaria (n = 37.8%), and bacterial sepsis (n = 32.7%). Nearly, half (35% invasive; 12% noninvasive) received mechanical ventilation, a quarter (23.4%) required vasoactive therapy in first 24 h and 9% received renal replacement therapy. Median (interquartile range) ICU and hospital length of stay were 4 (3-7) and 7 (5-11.3) days. At 28 days, 76.2% survived without disability, 4.4% had some disability, and 18.4% died. Mortality was higher (27% vs. 15%) in patients with undiagnosed etiology (P < 0.01). On multivariate analysis, multiorgan dysfunction syndrome at admission (odds ratio [95% confidence interval]-2.8 [1.8-6.6]), day 1 Sequential Organ Failure Assessment score (1.2 [1.0-1.3]), and the need for invasive ventilation (8.3 [3.4-20]) were the only independent predictors of unfavorable outcome.

Conclusions

Dengue, scrub typhus, encephalitis, and malaria are the major tropical fevers in Indian ICUs. The data support a syndromic approach, point of care tests, and empiric antimicrobial therapy recommended by Indian Society of Critical Care Medicine in 2014.

Deep sequencing approach for investigating infectious agents causing fever

Acute undifferentiated fever (AUF) poses a diagnostic challenge due to the variety of possible aetiologies. While the majority of AUFs resolve spontaneously, some cases become prolonged and cause significant morbidity and mortality, necessitating improved diagnostic methods. This study evaluated the utility of deep sequencing in fever investigation. DNA and RNA were isolated from plasma/sera of AUF cases being investigated at Cairns Hospital in northern Australia, including eight control samples from patients with a confirmed diagnosis. Following isolation, DNA and RNA were bulk amplified and RNA was reverse transcribed to cDNA. The resulting DNA and cDNA amplicons were subjected to deep sequencing on an Illumina HiSeq 2000 platform. Bioinformatics analysis was performed using the program Kraken and the CLC assembly-alignment pipeline. The results were compared with the outcomes of clinical tests. We generated between 4 and 20 million reads per sample. The results of Kraken and CLC analyses concurred with diagnoses obtained by other means in 87.5 % (7/8) and 25 % (2/8) of control samples, respectively. Some plausible causes of fever were identified in ten patients who remained undiagnosed following routine hospital investigations, including Escherichia coli bacteraemia and scrub typhus that eluded conventional tests. Achromobacter xylosoxidans, Alteromonas macleodii and Enterobacteria phage were prevalent in all samples. A deep sequencing approach of patient plasma/serum samples led to the identification of aetiological agents putatively implicated in AUFs and enabled the study of microbial diversity in human blood. The application of this approach in hospital practice is currently limited by sequencing input requirements and complicated data analysis.

Aetiologies of Acute Undifferentiated Febrile illness in Adult Patients - an Experience from a Tertiary Care Hospital in Northern India

INTRODUCTION

Acute undifferentiated febrile illness (AUFI) is a common clinical entity in most of the hospitals. The fever can be potentially fatal if the aetiology is not recognized and appropriately treated early.

AIM

To describe the aetiology of fever among patients in a tertiary care hospital in Northern India.

MATERIALS AND METHODS

A one-year retro-prospective, observational study was conducted in adults (age>18years) presenting with undifferentiated febrile illness (of duration 5-14 days). Diagnosis was confirmed by suitable laboratory tests after exhaustive clinical examination.

RESULTS

A total of 2547 patients with AUFI were evaluated. Of these, 1663 (65.3%) were males and 884 (34.7%) were females. Dengue (37.54%); enteric fever (16.5%); scrub typhus (14.42%); bacterial sepsis (10.3%); malaria (6.8%); hepatitis A (1.9%); hepatitis E (1.4%); leptospirosis (0.14%); were the main infections while no specific diagnosis could be delineated in 11%. Mixed infections were noted in 48 (1.9%) patients.

CONCLUSION

A good clinical acumen supported by the basic investigations can help diagnose the cause of fever with reasonable certainty.

Household Food Insecurity is Associated with Respiratory Infections Among 6-11-Month Old Infants in Rural Ghana

BACKGROUND

To determine the relationship between household food insecurity (HHFI) and symptoms of respiratory infections among infants in rural Ghana.

METHODS

The study was cross-sectional. The outcome variables were symptoms of respiratory infections (cough and nasal discharge) in infants. HHFI was measured using a 15-item modified U.S. Department of Agriculture (USDA) household food security module. Households were classified as food insecure if they had an affirmative answer for at least 1 item. Associations were examined using multiple logistic regression analysis. Data were collected in 32 communities located in 3 rural subdistricts in the Upper Manya Krobo district of the Eastern region of Ghana. The sample included 367 infants aged 6-11 months who attended a community-based growth monitoring session.

RESULTS

Overall, 20.5% of households reported experiencing food insecurity in the last month. Compared with infants in food secure households, infants living in food insecure households were about twice as likely to experience cough (adjusted odds ratio: 2.25, 95% confidence intervals: 1.25, 4.04) and nasal discharge (adjusted odds ratio: 1.87, 95% confidence intervals: 1.05, 3.36).

CONCLUSION

Infants living in food insecure households are at an increased risk of respiratory tract morbidity. Interventions that address HHFI might be important to improve infant health in rural Ghana.

Antibiotic prescribing in medical intensive care units--a comparison between two private sector hospitals in Central India

BACKGROUND

Inappropriate antibiotic prescribing, common in India, contributes to increased risk for development of bacterial resistance. Patients admitted to intensive care units (ICUs) are often prescribed antibiotics. Paucity of local data on antibiotic prescribing hinders development of appropriate interventions. The aim of the study was to describe and compare antibiotic prescribing in medical ICUs (MICUs) at two private sector hospitals, one teaching (TH) and one non-teaching (NTH) in Ujjain, India.

METHODS

The study was conducted prospectively for 3 years at MICUs of both hospitals. Patients were compared for demographic variables and diagnosis, prescribed antibiotics, generic name prescribing, and route of administration. Adherence to the World Health Organization list of essential medicines (WHOLEM) and the National List of Essential Medicines of India (NLEMI) was analyzed.

RESULTS

In total, 4843 of 6141 patients admitted to the MICUs stayed at least one night. More than 70% were prescribed antibiotics. Generic name prescribing was more common at the TH than at the NTH. Prescriptions at the TH had higher compliance to WHOLEM and NLEMI compared with that at the NTH (p < 0.001). Of the 1371 patients at the TH, 189 (14%) and of 3472 at the NTH, 400 (12%) patients were diagnosed with infections. More than 75% of patients at both hospitals had no infection-associated diagnoses.

CONCLUSIONS

Antibiotic prescribing was common at both hospitals. The antibiotic prescriptions at the TH had higher compliance to WHOLEM and NLEMI. However, there is a need to develop appropriate interventions to improve antibiotic prescribing at both hospitals.

Estimating the spatial distribution of acute undifferentiated fever (AUF) and associated risk factors using emergency call data in India. A symptom-based approach for public health surveillance

The System for Early-warning based on Emergency Data (SEED) is a pilot project to evaluate the use of emergency call data with the main complaint acute undifferentiated fever (AUF) for syndromic surveillance in India. While spatio-temporal methods provide signals to detect potential disease outbreaks, additional information about socio-ecological exposure factors and the main population at risk is necessary for evidence-based public health interventions and future preparedness strategies. The goal of this study is to investigate whether a spatial epidemiological analysis at the ecological level provides information on urban-rural inequalities, socio-ecological exposure factors and the main population at risk for AUF. Our results displayed higher risks in rural areas with strong local variation. Household industries and proximity to forests were the main socio-ecological exposure factors and scheduled tribes were the main population at risk for AUF. These results provide additional information for syndromic surveillance and could be used for evidence-based public health interventions and future preparedness strategies.

Validation of a clinical risk-scoring algorithm for severe scrub typhus

OBJECTIVE

The aim of the study reported here was to validate the risk-scoring algorithm for prognostication of scrub typhus severity.

METHODS

The risk-scoring algorithm for prognostication of scrub typhus severity developed earlier from two general hospitals in Thailand was validated using an independent dataset of scrub typhus patients in one of the hospitals from a few years later. The predictive performances of the two datasets were compared by analysis of the area under the receiver-operating characteristic curve (AuROC). Classification of patients into non-severe, severe, and fatal cases was also compared.

RESULTS

The proportions of non-severe, severe, and fatal patients by operational definition were similar between the development and validation datasets. Patient, clinical, and laboratory profiles were also similar. Scores were similar in both datasets, both in terms of discriminating non-severe from severe and fatal patients (AuROC =88.74% versus 91.48%, P=0.324), and in discriminating fatal from severe and non-severe patients (AuROC =88.66% versus 91.22%, P=0.407). Over- and under-estimations were similar and were clinically acceptable.

CONCLUSION

The previously developed risk-scoring algorithm for prognostication of scrub typhus severity performed similarly with the validation data and the first dataset. The scoring algorithm may help in the prognostication of patients according to their severity in routine clinical practice. Clinicians may use this scoring system to help make decisions about more intensive investigations and appropriate treatments.

Tropical fevers: Management guidelines

Tropical fevers were defined as infections that are prevalent in, or are unique to tropical and subtropical regions. Some of these occur throughout the year and some especially in rainy and post-rainy season. Concerned about high prevalence and morbidity and mortality caused by these infections, and overlapping clinical presentations, difficulties in arriving at specific diagnoses and need for early empiric treatment, Indian Society of Critical Care Medicine (ISCCM) constituted an expert committee to develop a consensus statement and guidelines for management of these diseases in the emergency and critical care. The committee decided to focus on most common infections on the basis of available epidemiologic data from India and overall experience of the group. These included dengue hemorrhagic fever, rickettsial infections/scrub typhus, malaria (usually falciparum), typhoid, and leptospira bacterial sepsis and common viral infections like influenza. The committee recommends a 'syndromic approach' to diagnosis and treatment of critical tropical infections and has identified five major clinical syndromes: undifferentiated fever, fever with rash / thrombocytopenia, fever with acute respiratory distress syndrome (ARDS), fever with encephalopathy and fever with multi organ dysfunction syndrome. Evidence based algorithms are presented to guide critical care specialists to choose reliable rapid diagnostic modalities and early empiric therapy based on clinical syndromes.

A multiplex nested PCR for the simultaneous detection of Salmonella typhi, Mycobacterium tuberculosis, and Burkholderia pseudomallei in patients with pyrexia of unknown origin (PUO) in Vellore, South India

BACKGROUND AND OBJECTIVES

Salmonella typhi, Mycobacterium tuberculosis, and Burkholderia pseudomallei are among the most important monocyte-tropic bacterial agents causing pyrexia of unknown origin (PUO), with a significant number of endemic infections in both South and Southeast Asian regions. These infections pose a major risk to travelers to these regions as well.

METHODS

We developed and evaluated a multiplex nested polymerase chain reaction (PCR) for the simultaneous detection of the three pathogens in 305 patients' buffy coat samples.

RESULTS

The assay for S. typhi and B. pseudomallei was able to detect down to 1 colony forming unit/5 μL PCR input and M. tuberculosis was detected down to 20 genome copies/5 μL PCR input. S. typhi was detected in 10 (3.3 %) individuals, B. pseudomallei in 10 individuals (3.3 %), and M. tuberculosis in 18 individuals (5.9 %). Co-infections of M. tuberculosis and B. pseudomallei were detected in three individuals and S. typhi and B. pseudomallei in two individuals.

CONCLUSION

This protocol is efficient for PUO diagnosis especially in Asian countries.