Comparison between the demographic shift clinical severity and outcome of the first two waves of COVID-19 in pregnancy in a tertiary hospital in India.

OBJECTIVE: To study and compare the maternal and neonatal outcomes of COVID-19 in pregnancy during the two waves of the pandemic in India. METHODS: This observational, retrospective cohort study on pregnant women with SARS-CoV-2 infection was conducted in a 2700-bed tertiary referral center in South India from March 1, 2020 to June 30 2021. The clinical presentation, severity, and maternal and neonatal outcomes of COVID-19 were compared between the two waves. RESULTS: A total of 623 pregnant women tested positive for SARS-CoV-2 infection in our institute; 379 (60.8%) were diagnosed during the first wave and 244 (39.2%) in the second wave. Most of the affected women (81.1%) were in their third trimester. Maternal mortality rate was 823 per 100 000 live births. Composite maternal outcome (increasing requirement for ventilation, pulmonary embolism, disease progression) were more pronounced during the second wave (2.1% vs 6.1%). Between the two waves, both maternal (1 vs 3; P = 0.162) and perinatal (3.2% vs 6.7%; P = 0.065) deaths were higher during the second wave. The cesarean section rate was high during the first wave (48% vs 32.4%; P < 0.001). Preterm births were comparable between the two waves (19.5% vs 22%; P < 0.500). CONCLUSION: The women presented with more severe illness during the second wave of COVID-19. There was higher perinatal mortality, but the maternal mortality was similar between the two waves.

Evaluation of Remdesivir to the outcomes of hospitalized patients with COVID-19 infection in a tertiary-care hospital in southern India.

INTRODUCTION: Remdesivir was the only antiviral used in the treatment of COVID-19 in the first wave of the COVID-19 pandemic, following the adaptive COVID-19 treatment trial-1 interim analysis report. However, its use in moderate to critical hospitalized COVID-19 patients continues to be controversial. METHODOLOGY: In a cohort of 1,531 moderate to critical COVID-19 patients, we retrospectively performed a nested case-control study where 515 patients on Remdesivir were compared to 411 patients with no Remdesivir. Cases and controls were matched for age, sex and severity. The primary outcome was in-hospital mortality and secondary outcomes were duration of hospital stay, need for intensive care unit (ICU), progression to oxygen therapy, progression to non-invasive ventilation, progression to mechanical ventilation, and duration of ventilation. RESULTS: Mean age of the cohort was 57.05 + 13.5 years. 75.92% were males. Overall, in-hospital mortality was 22.46% (n = 208). There was no statistically significant difference in all-cause mortality among cases and controls (20.78% vs. 24.57%, p = 0.17). Progression to non-invasive ventilation was lower in the Remdesivir group (13.6% vs 23.7%, p < 0.001), however progression to mechanical ventilation was higher in the Remdesivir group (11.3% vs 2.7%, p value < 0.001*). In a subgroup analysis of critically ill patients, the use of Remdesivir lowered mortality (OR 0.32 95% CI: 0.13 - 0.75). CONCLUSIONS: Remdesivir did not decrease the in-hospital mortality in moderate to severe COVID-19 but decreased progression to non-invasive ventilation. Its mortality benefit in critically ill patients needs further evaluation. Remdesivir may be useful if given early in the treatment of patients with moderate COVID-19.

Impact of prior vaccination with CovishieldTM and Covaxin® on mortality among symptomatic COVID-19 patients during the second wave of the pandemic in South India during April and May 2021: a cohort study.

BACKGROUND: COVID-19 vaccines were authorised for emergency use to mitigate the impact of the pandemic. This study evaluated the effect of prior vaccination with either Oxford Astra Zeneca's Covishield™ or Bharath Biotech's Covaxin® on mortality among symptomatic COVID-19 patients during the second wave of the pandemic in India. METHODOLOGY: In this cohort study comprising of RT-PCR confirmed symptomatic COVID-19 patients presenting during April and May 2021, the effect of prior vaccination on mortality (primary outcome), need for hospitalization, oxygen therapy, non-invasive ventilation (NIV) and intensive care unit (ICU) admission were assessed and expressed as risk ratio (RR) with 95% confidence intervals (CI). RESULTS: The mean (SD) age of the cohort (n = 4183) was 46.3 (15.5) years; 17.9% (748/4183) had received at least one dose of Covishield™ and 4.8% (201/4183) had received Covaxin®. Mortality was 0.2% (95% CI: 0.2% - 0.7%), 3.5% (1.9-5.2%), 6.2% (0.3-12%) and 12.9% (11.8-14.1%) among fully vaccinated (>2 weeks after two doses), partially vaccinated (>2 weeks after one dose or <2 weeks after two doses), indeterminate (<2 weeks after one dose) and unvaccinated patients respectively. The difference in mortality among unvaccinated vs. fully vaccinated was 12.7% (95% CI: 11.4-13.9%), unvaccinated vs. partially vaccinated was 9.4% (7.4-11.4%) and unvaccinated vs. indeterminate vaccinated was 6.8% (0.8-12.7%). On adjusted analysis, as compared to unvaccinated patients, at least one dose of vaccine reduced the need for hospitalization (RR: 0.40; 95% CI: 0.35-0.47), oxygen (0.33; 0.27-0.40), NIV (0.23; 0.17-0.32), ICU admission (0.18; 0.12-0.27) and mortality (0.18; 0.11-0.29). CONCLUSION: Among symptomatic COVID-19 patients, prior vaccination with Covishield ™ or Covaxin® impacted the severity of illness and reduced mortality during a period of widespread delta variant circulation. Full vaccination conferred greater protection than partial vaccination.

Stenotrophomonas isolates in a tertiary care centre in South India.

PURPOSE: Stenotrophomonas maltophilia is an emerging multi-drug resistant pathogen increasingly isolated in India. This study aimed to identify patients from whom Stenotrophomonas maltophilia had been isolated and assess predictors of mortality in this population. METHODS: This was a retrospective cohort study of hospitalized patients with a positive culture for S. maltophilia over a 3-year period. Clinical details and laboratory results were assessed from hospital records. Bivariate and multivariate analysis was used to identify risk factors for mortality. RESULTS: One hundred and nineteen patients (mean age 48.6 years) were included in the study. Of these, 111 patients were hospitalized for at least 48 â€‹hours prior to culture and 98 were admitted in the intensive care unit. Bivariate analysis revealed multiple associations with mortality, including a background of renal, cardiac, autoimmune disease, recent carbapenam use and COVID-19 infection and increasing ventilatory requirement, lower PaO2/FiO2 (P/F) ratio, vasopressor use, thrombocytopenia, and hypoalbuminemia at the time of positive isolate. Multivariate analysis showed that autoimmune disease [OR 27.38; 95% CI (1.39-540)], a P/F ratio of less than 300 [OR 7.58; 95% CI (1.52-37.9)], vasopressor requirement [OR 39.50; 95% CI (5.49-284)] and thrombocytopenia [OR 11.5; 95% CI (2.04-65.0)] were statistically significantly associated with increased mortality, while recent surgery and receipt of antibiotics [OR 0.16; 95% CI (0.03-0.8)] targeted against S. maltophilia were associated with decreased mortality. CONCLUSION: Stenotrophomonas maltophilia is primarily isolated in patients in the intensive care unit. In our study the need for vasopressors, autoimmune disease, lower P/F ratios and thrombocytopenia were associated with higher mortality. The association of targeted antibiotics with reduced mortality suggests that the pathogenic role of S. maltophilia should not be underestimated. This finding needs to be confirmed with larger, prospective studies.

Predicting antitubercular drug-induced liver injury and its outcome and introducing a novel scoring system.

Background: Tuberculosis (TB) is a major global health problem, mainly in developing countries. Despite the availability of highly effective first-line antitubercular (ATT) drugs, ATT drug-induced liver injury (ATT DILI) leads to treatment interruption and consequently loss of therapeutic efficacy. Methods: In this prospective cohort study from India, all consecutive patients who met inclusion criteria and started on ATT were included. The incidence, risk factors, and outcome of ATT DILI were determined. A clinical prediction score for ATT DILI was derived. Results: A total of 393 patients were included. The incidence of ATT DILI was 9.7% (95% confidence interval 7%-13.2%). HIV infection, daily regimen, disseminated disease, and chronic liver disease were identified as significant risk factors (P < 0.05) for developing DILI. A prediction score derived from the risk factors showed that a score of >5 could predict DILI with a sensitivity of 74% and a specificity of 67%. All-cause mortality in DILI was 4.7%. Conclusion: The incidence of ATT DILI was 9.7% in our cohort with higher incidence among the patients on daily regimen. The study suggests that the combination of risk factors of extensive TB disease, HIV infection, chronic liver disease, and under nutrition increases the vulnerability to DILI, particularly with daily treatment regimen, emphasizing the role of acquired risk factors in the development of DILI.

Intravenous colistin for the management of multidrug-resistant bacterial infections in Indian patients.

Multidrug-resistant Gram-negative bacterial infection is a serious global concern and especially in low and middle-income countries (LMIC) such as India. Colistin, an antimicrobial once abandoned following reports of organ toxicity, has re-emerged as an essential therapeutic agent in the management of these infections. A retrospective review of 162 inpatients was done, focusing on culture-proven multidrug-resistant infections requiring colistin. The overall clinical outcome in 58% of patients was found to be good, with nephrotoxicity and neurotoxicity occurring only in 8 (5%) and 4 (2.5%) patients, respectively. Multivariate analysis revealed an elevated lactate and raised urea to be independent factors associated with poor clinical response. In conclusion, there appears to be strong evidence supporting the use of colistin in the management of multidrug-resistant Gram-negative bacterial infections.

Gram-negative infective endocarditis: a retrospective analysis of 10 years data on clinical spectrum, risk factor and outcome.

Infective endocarditis (IE) is a significant cause of morbidity and mortality. Underlying congenital heart disease and acquired valvular disease significantly increases the IE risk, which is still prevalent in developing countries. Gram-negative organism related IE prevalence appears to be rising with limited data on their presentation and outcomes. This study hopes to shed further light on this subject. This retrospective cross-sectional study occurred in a tertiary care center in South India. A retrospective cross-sectional study performed in a single tertiary care center in South India. All patients with IE from 2006 to 2016 were included in this study. The details of clinical presentation, laboratory investigations, clinical course, microbiology, and outcomes were obtained. Patients fulfilling the modified Duke's criteria and a culture-proven diagnosis of gram-negative IE were eligible for inclusion. A total of 27 patients were enrolled from Jan 2006 to Dec 2016, among whom 78% were male. Prior structural heart disease was common in our cohort (41%) with renal (55%) and embolic (51%) complications being the most common systemic complications. A comparison of mortality with survivors found that congenital and acquired structural heart disease had a higher risk of mortality. Non-fermenting GNB accounted for 52% of the cohort, with Pseudomonas accounting for 19%. E. coli was the most common bacilli isolated, constituting 37% of the cohort. Assessment of risk factors for adverse outcomes found that renal dysfunction and intravascular device were significant with multivariate-logarithmic analysis showing renal dysfunction as an independent risk factor. In-hospital mortality in this series was 30%. In conclusion, gram-negative IE was more prevalent among males. Underlying structural heart disease was the most common risk factor associated with the disease. Renal dysfunction and embolic complications were the most common complications in this cohort. E. coli and NFGNB accounted for 70% of the offending organisms. In-hospital mortality was similar to patients with IE secondary to common organisms. The presence of renal dysfunction was an independent risk factor for an adverse outcome.

Effectiveness of treatment regimens for Typhoid fever in the nalidixic acid-resistant S. typhi (NARST) era in South India.

The epidemiology of typhoid fever in South Asia has changed. Multi-drug resistant (MDR) Salmonella typhi ( S. typhi) is now frequently resistant to nalidixic acid and thus labelled NARST. Treatment failure with the use of fluoroquinolones has been widely noted, forcing clinicians to adopt alternative treatment strategies. In this observational study, we looked at various treatment regimens and correlated clinical and microbiological outcomes. In 146 hospitalised adults, the median minimum inhibitory concentration (MIC) for ciprofloxacin was 0.38 µg/mL with a median fever clearance time (FCT) of eight days (range = 2-35 days). Of the regimens used, gatifloxacin and azithromycin had a shorter FCT of six days compared to ceftriaxone (ten days; P < 0.001). Though mortality and relapse in our cohort was low, NARST seemed to correlate with mortality ( P = 0.006). Gatifloxacin or azithromycin clearly emerge as the drugs of choice for treatment of typhoid in South India.

Mycobacterial blood culture as the only means of diagnosis of disseminated tuberculosis in advanced HIV infection.

The diagnosis of disseminated tuberculosis (TB) in advanced HIV infection is often delayed because of difficulty in obtaining suitable specimens for culture. A total of 32 such patients from South India with positive mycobacterial blood cultures were studied over ten years. Almost all (90%) had a febrile illness and the majority (68.7%) had clinical lung involvement, but only 27.3% had positive sputum smears. Liver biopsy yielded a positive diagnosis in only 1/7. Cytopenia was almost universal (96.9%). Bone marrow cultures were, however, positive in 54.8%, of whom one-quarter grew atypical mycobacteria. Mycobacterial blood culture is therefore a useful adjunct test to diagnose TB in advanced HIV.

Clinical spectrum of yellow phosphorous poisoning in a tertiary care centre in South India: a case series.

Rodenticides such as yellow phosphorus are highly toxic compounds which are commonly used for pest control. Reports of yellow phosphorus poisoning from tropical nations is scanty. In this retrospective study, we report the clinical features, mortality and predictors of mortality among nine patients at a tertiary care centre in south India. Yellow phosphorus consumption was common among a younger age group of patients. The mean duration of presentation after consumption was five days. The most common clinical manifestations seen were abdominal pain and vomiting followed by a depressed sensorium. Features of acute liver failure including coagulopathy were seen in all patients. Despite all patients receiving supportive therapy, a poor outcome or death resulted in the majority. Early referral to a tertiary care centre, meticulous monitoring and supportive measures are key elements of patient management as there are no specific antidotes available at present. Increase in public and physician awareness to the toxin and implementation of preventive policies is of utmost importance.

Prevalence of Toxin Genes among the Clinical Isolates of Staphylococcus aureus and its Clinical Impact.

INTRODUCTION: Staphylococcus aureus (S. aureus) causes a variety of infections, ranging from a mild skin infection to blood stream infections and deep seated infections. As Stapylococcus aureus bacteremia (SAB) has the tendency to cause endovascular and metastatic infections, complications can occur at almost all sites of the body. Hence, SAB is associated with increased morbidity and mortality in spite of appropriate antimicrobial treatment. The virulence in S. aureus is determined by the presence of adhesins and toxins, which behave like superantigens (SAgs) and leads to a massive release of proinflammatory cytokines causing overwhelming inflammatory response leading to endothelial leakage, hemodynamic shock, multiorgan failure, and possibly death. MATERIALS AND METHODS: One year prospective study conducted in a tertiary care hospital in southern part of India included all patients with SAB. Clinical details were filled according to. All isolates were subjected to polymerase chain reaction (PCR) for enterotoxin profiling. RESULTS: A total of 101 patients of SAB were identified which comprises of 61 (60.4%) patients with methicillin-susceptible S. aureus (MSSA) and 40 (39.6%) patients with methicillin-resistant S. aureus (MRSA). Most common predictors of mortality were prior hospitalization and antibiotic intake, severe organ dysfunction, shock, tachycardia, and leukocytosis. Two-third of the isolates had at least one enterotoxin, most prevalent was sea; 28% and 27% (P - value = 0.001) MSSA isolates had seg and sei; whereas, 38.6% (P - value < 0.001) of MRSA isolates were found to have sea. The most common enterotoxin associated with mortality was sei, which comprised of 38% of all mortality. CONCLUSION: In SAB, the significant predictors of mortality were prior hospitalization and antibiotic intake, presence of multiorgan dysfunction, and shock. Although overall significance between the enterotoxin and shock could not be demonstrated, it successfully demonstrated the difference of enterotoxin between MSSA and MRSA.

Scrub typhus meningitis: An under-recognized cause of aseptic meningitis in India.

BACKGROUND: Central nervous system (CNS) involvement in scrub typhus is seen in up to a quarter of patients. However, the literature on cerebrospinal fluid (CSF) analysis and outcome in meningitis/meningo-encephalitis due to scrub typhus is scant. MATERIALS AND METHODS: This retrospective study included patients who were admitted to a medical college hospital with scrub typhus meningitis/meningo-encephalitis between 2005 and 2011. The clinical and laboratory profile, details of CSF analysis and outcome were documented. RESULTS: The study included 189 patients with meningitis/meningo-encephalitis due to scrub typhus. The mean age of the patients was 41 ± 4 years. The mean duration of fever before presentation was 9.4 ± 3 days. The common presenting complaints were headache (64.2%), nausea/vomiting (60%), altered sensorium (53.7%) and seizures (22.1%). The presence of an eschar was documented in 27.5% of the patients. The mean CSF white blood count was 80 cells/cu mm (range: 5-740). There was a clear lymphocyte predominance (mean 87.6%). The mean CSF protein level was 105 mg% (range: 13-640). The mean CSF sugar level was 63.9 mg% (range 25-350), and was less than 40 mg% in 11.1% of the cases. The case fatality rate was 5.8% (11/189). Univariate analysis showed the presence of an eschar (15.4% vs 2.2%; Odds Ratio [OR]: 8.1) and altered sensorium (9.8% vs 1.1%; OR: 9.2) to be significant predictors of mortality. CONCLUSIONS: In endemic regions, scrub typhus should be considered in the differential diagnosis of aseptic meningitis. Modest elevation of cells in the CSF with lymphocytic pleocytosis and multi-organ involvement may indicate scrub typhus meningitis/meningo-encephalitis.

Cost-utility in medical intensive care patients. Rationalizing ongoing care and timing of discharge from intensive care.

RATIONALE: Intensive care unit (ICU) treatment costs pose special challenges in developing countries. OBJECTIVES: To determine the prognostic value of the "utility" score and evaluate the relationship of willingness to pay assessment to utility score during ICU admission. METHODS: We performed a prospective study spanning 12 months in a 24-bed medical ICU in India. Treatment cost was estimated by direct measurement. Global utility score was assessed daily by healthcare providers on a Likert scale (0-1 in increments of 0.1, with 0 indicating death/severe disability and 1 indicating cure/perfect health). The sensitivity, specificity, and likelihood ratios of utility in predicting ICU mortality was calculated. Receiver operating characteristic curves were generated to compare Day 2 utility with APACHE II. The caregiver's willingness to pay for treatment was assessed on alternate days using the bidding method by presenting a cost bid. Based on the response ("yes" or "no"), bids were increased or decreased in a prespecified manner until a final bid value was reached. Simultaneously, treating doctors were asked how much institutional funds they would be willing to spend for treatment. MEASUREMENTS AND MAIN RESULTS: Primary diagnosis in 499 patients included infection (26%) and poisoning (21%). The mean (SD) APACHE II score was 13.9 (5.8); 86% were ventilated. ICU stay was 7.8 (5.5) days. ICU mortality was 23.9% (95% confidence interval, 20.3-27.8). Survival without disability was 8.3% (2/24) for Day 2 utility score ≤0.3 and 95.8% (53/56) for Day 5 score >0.8 (P < 0.001). The likelihood ratio to predict mortality increased as utility values decreased and was highest (5.85) for utility 0.2. Area under the receiver operating characteristic curves for utility and APACHE II were similar. Willingness to pay by the caregiver was 53% of treatment cost and was not influenced by utility. Willingness to pay by ICU doctors showed an inverted U-shaped relationship with utility. CONCLUSIONS: Utility scores help prognosticate, with Day 2 score ≤0.3 associated with poor outcome and ≥0.8 Day 5 score with survival. The caregiver's willingness to pay was inadequate to meet treatment cost. ICU doctors were willing to spend more for moderate utility scores than for very high or low utility values. Further prospective studies are needed to optimize the utilization of scarce ICU resources by identifying patients for appropriate step-down care using utility and willingness to pay.

Prospective multi-centre sentinel surveillance for Haemophilus influenzae type b & other bacterial meningitis in Indian children.

BACKGROUND & OBJECTIVES: Haemophilus influenzae type b (Hib) is one of the leading bacterial causes of invasive disease in populations without access to Hib conjugate vaccines (Hib-CV). India has recently decided to introduce Hib-CV into the routine immunization programme in selected States. Longitudinal data quantifying the burden of bacterial meningitis and the proportion of disease caused by various bacteria are needed to track the impact of Hib-CV once introduced. A hospital-based sentinel surveillance network was established at four places in the country and this study reports the results of this ongoing surveillance. METHODS: Children aged 1 to 23 months with suspected bacterial meningitis were enrolled in Chennai, Lucknow, New Delhi, and Vellore between July 2008 and June 2010. All cerebrospinal fluid (CSF) samples were tested using cytological, biochemical, and culture methods. Samples with abnormal CSF (≥10 WBC per µl) were tested by latex agglutination test for common paediatric bacterial meningitis pathogens. RESULTS: A total of 708 patients with abnormal CSF were identified, 89 of whom had a bacterial pathogen confirmed. Hib accounted for the majority of bacteriologically confirmed cases, 62 (70%), while Streptococcus pneumoniae and group B Streptococcus were identified in 12 (13%) and seven (8%) cases, respectively. The other eight cases were a mix of other bacteria. The proportion of abnormal CSF and probable bacterial meningitis that was caused by Hib was 74 and 58 per cent lower at Christian Medical College (CMC), Vellore, which had a 41 per cent coverage of Hib-CV among all suspected meningitis cases, compared to the combined average proportion at the other three centres where a coverage between 1 and 8 per cent was seen (P<0.001 and P= 0.05, respectively). INTERPRETATION & CONCLUSIONS: Hib was found to be the predominant cause of bacterial meningitis in young children in diverse geographic locations in India. Possible indications of herd immunity was seen at CMC compared to sites with low immunization coverage with Hib-CV. As Hib is the most common pathogen in bacterial meningitis, Hib-CV would have a large impact on bacterial meningitis in Indian children.

Invasive pneumococcal disease associated with high case fatality in India.

OBJECTIVE: To study the seroepidemiology and antimicrobial resistance pattern of invasive pneumococcal disease (IPD) in older subjects who are admitted to hospitals in India. STUDY DESIGN AND SETTING: Prospective surveillance of IPD in patients older than 18 years in seven large academic teaching hospitals in India from 1993 to 2008. All subjects who had Streptococcus pneumoniae isolated from normally sterile body fluids or were antigen positive in cerebrospinal fluid, ascitic fluid, and pleural fluid were identified as IPD cases in the study. Serotype/group (STG) and minimum inhibitory concentration for penicillin, chloramphenicol, co-trimoxazole (trimethoprim-sulfamethoxazole), erythromycin, and cefotaxime were determined. RESULTS: A total of 1,037 adult subjects with suspected invasive bacterial infection were recruited in the study. S pneumoniae was identified from normally sterile body fluids in 449 (43.3%) subjects. Meningitis (34.3%) and pneumonia (33.9%) were the most common clinical conditions associated with IPD. The case fatality was 25-30% across all age groups. Penicillin resistance was low at 2.7% overall. Resistance to co-trimoxazole was noted to be high and increasing in the study period from 42.9% in 1993 to 85.2% in 2008 (P = 0.001). The most common STG was serotype 1, which accounted for 22.9% of all isolates. The 23-valent pneumococcal polysaccharide vaccine covered 83.3% of the STGs (49/54; 95% confidence interval: 79.7, 96.9) for patients older than 60 years. CONCLUSION: IPD continues to be a problem in India and is associated with high case fatality in spite of treatment in the hospital setting. Penicillin resistance is currently low in India. More than 80% of invasive STGs causing disease in the elderly in India are included in the formulation of polysaccharide pneumococcal vaccine.

A clinical study of renal tubular dysfunction in Cleistanthus collinus (Oduvanthalai) poisoning.

INTRODUCTION: Self-poisoning through the ingestion of Oduvanthalai is common in South India. Mortality may occur because of arrhythmias, renal failure, shock, and respiratory distress. The mechanisms of toxicity are unclear. This prospective, clinical study was designed to assess renal tubular dysfunction because of Oduvanthalai poisoning. METHODS: Thirty-two consecutive patients admitted with Oduvanthalai poisoning at a tertiary care hospital in South India, from June 2007 to August 2009 (26 months), were evaluated through history, physical examination, and laboratory studies. Following an interim analysis, additional studies of renal tubular function were performed on a subcohort of eight patients. These included the following: (1) urinary pH, daily serum, and urine anion gap; (2) 24-h urine protein and potassium; and (3) assessment of urine hexosaminidase and amino acid levels. RESULTS: Metabolic acidosis (100%), which persisted at discharge (65.6%), hypokalemia (62.5%), and renal failure (15.6%), was apparent in the total cohort. Tests of renal tubular function on the subcohort revealed a normal anion gap, hyperchloremic, metabolic acidosis of renal etiology, defective urinary acidification, and hypokalemia with kaliuresis, indicative of distal renal tubular acidosis in six patients. Urinary hexosaminidase and amino acid levels, markers of proximal tubular dysfunction, were elevated in seven and two patients, respectively. CONCLUSIONS: Distal renal tubular acidosis is an important feature of Oduvanthalai poisoning. Proximal tubular injury and, in more severe forms, global tubular dysfunction with diminished glomerular filtration rate may occur.