Ramya Iyyadurai

Profile of organ dysfunction and predictors of mortality in severe scrub typhus infection requiring intensive care admission

Background and Aims: Scrub typhus, a zoonotic rickettsial infection, is an important reason for intensive care unit (ICU) admission in the Indian subcontinent. We describe the clinical profile, organ dysfunction, and predictors of mortality of severe scrub typhus infection. Materials and Methods: Retrospective study of patients admitted with scrub typhus infection to a tertiary care university affiliated teaching hospital in India during a 21-month period. Results: The cohort (n = 116) aged 40.0 ± 15.2 years (mean ± SD), presented 8.5 ± 4.4 days after symptom onset. Common symptoms included fever (100%), breathlessness (68.5%), and altered mental status (25.5%). Forty-seven (41.6%) patients had an eschar. Admission APACHE-II score was 19.6 ± 8.2. Ninety-one (85.2%) patients had dysfunction of 3 or more organ systems. Respiratory (96.6%) and hematological (86.2%) dysfunction were frequent. Mechanical ventilation was required in 102 (87.9%) patients, of whom 14 (12.1%) were solely managed with non-invasive ventilation. Thirteen patients (11.2%) required dialysis. Duration of hospital stay was 10.7 ± 9.7 days. Actual hospital mortality (24.1%) was less than predicted APACHE-II mortality (36%; 95% Confidence interval 32-41). APACHE-II score and duration of fever were independently associated with mortality on logistic regression analysis. Conclusions: In this cohort of severe scrub typhus infection with multi-organ dysfunction, survival was good despite high severity of illness scores. APACHE-II score and duration of fever independently predicted mortality.

Imidacloprid Poisoning—Newer Insecticide and Fatal Toxicity

To the Editor, There is a constant search for new and potent insecticides nontoxic to humans. We describe fatal toxicity with one such insecticide considered relatively safe. A 34-year-old male from rural India was brought following the deliberate consumption of imidacloprid in a suicide attempt. At presentation, he was comatose with dilated nonreacting pupils, diaphoretic, and cyanosed. His blood pressure was unrecordable, and his heart rate was 50/min. Following intubation and stabilization of hemodynamics with crystalloids, a gastric lavage was performed. Subsequently, he was referred to our hospital. On arrival, 2 h later, he continued to be unconscious with fixed dilated pupils. His blood pressure was 130/80 mmHg and pulse rate 86/min. Following transfer to intensive care, he required epinephrine infusion to maintain blood pressure. Deterioration of renal function was noted from the second day with progressive oligoanuria (peak creatinine 6.9 mg/dl) and severe metabolic acidosis necessitating dialysis. Creatinine phosphokinase levels of 67,980 U/L (reference<170 U/L) suggested rhabdomyolysis. Hospital stay was further complicated by the development of liver dysfunction, ventilator-associated pneumonia, and refractory septic shock. Despite appropriate supportive therapy, he succumbed on day12. Neonicotinoids, agonists at the nicotinic acetylcholine receptors (nAChRs), induce neuromuscular paralysis. The high selectivity for nAChRs (particularly the a4b2 subtype) in insects compared with mammals results in their favorable toxicological profile [1, 2]. Imidacloprid, the commonest neonicotinoid used in South Asia, was recently reported to have a 0% case fatality in a series of 68 patients presenting with poisoning [3]. Despite their safety profile, other publications have described rhabdomyolysis [4], neuropsychiatric manifestations [4], ventricular fibrillation [5], and deaths with imidacloprid [5–7]. This patient manifested neurological dysfunction and rhabdomyolysis. The initial neurological dysfunction, probably due to central nicotinic stimulation, was compounded by ischemic and metabolic encephalopathy. Renal injury was perpetuated by rhabdomyolysis, hypotension, and toxin. Progressive deterioration and eventual demise was due to multiple organ dysfunction syndrome and not the toxin per se. Serum imidacloprid level would have helped elucidate causality, but was unavailable. This report of imidacloprid toxicity sensitizes clinicians to an emerging cause of poisoning and highlights the need for a careful review of its toxicity profile.

Performance of clinical scoring systems in acute organophosphate poisoning

Abstract Introduction. Clinical scoring systems are used to predict mortality rate in hospitalized patients. Their utility in organophosphate (OP) poisoning has not been well studied. Methods. In this retrospective study of 396 patients, we evaluated the performance of the Acute Physiology and Chronic Health Evaluation (APACHE) II score, the Simplified Acute Physiology Score (SAPS) II, Mortality Prediction Model (MPM) II, and the Poisoning Severity Score (PSS). Demographic, laboratory, and survival data were recorded. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was calculated to study the relationship between individual scores and mortality rate. Results. The mean (standard deviation) age of the patients was 31.4 (12.7) years, and at admission, their pseudocholinesterase (median, interquartile) level was 317 (222–635) U/L. Mechanical ventilation was required in 65.7% of the patients and the overall mortality rate was 13.1%. The mean (95% confidence interval) scores were as follows: APACHE-II score, 16.4 (15.5–17.3); SAPS-II, 34.4 (32.5–36.2); MPM-II score, 28.6 (25.7–31.5); and PSS, 2.4 (2.3–2.5). Overall, the AUC for mortality was significantly higher for APACHE-II (0.77) and SAPS-II (0.77) than the PSS (0.67). When patients were categorized, the AUCs were better for WHO Class II (0.71–0.82) than that for Class I compounds (0.60–0.66). For individual compounds, the AUC for APACHE-II was highest in quinalphos (0.93, n = 46) and chlorpyrifos (0.86, n = 38) and lowest in monocrotophos (0.60, n = 63). AUCs for SAPS-II and MPM-II were marginally but not significantly lower than those for APACHE-II. The PSS was generally a poorer discriminator compared to the other scoring systems across all categories. Conclusions. In acute OP poisoning, the generic scoring systems APACHE-II and SAPS-II outperform the PSS. These tools may be used to predict the mortality rate in OP poisoning.

Organophosphate-pyrethroid combination pesticides may be associated with increased toxicity in human poisoning compared to either pesticide alone

Abstract Background. Organophosphate (OP) poisoning results in significant toxicity while pyrethroid poisoning is associated with extremely low fatality. OPs can inhibit the detoxification of pyrethroid and increase the toxicity of the combination. We assessed whether mixed OP-pyrethroid poisoning impacted outcome in human poisoning. Methods. Patients were identified from a prospectively collected institutional poisoning database that incorporates demographic and outcome data of patients presenting with poisoning. Results. Of the 1177 poisoned patients admitted over 2 years, 32 presented with OP-pyrethroid (50% chlorpyrifos-5% cypermethrin mixture) poisoning (Group 1), 26 consumed 20% chlorpyrifos (Group 2), and 32 took 15% cypermethrin (Group 3). Seizures occurred in 15.6% (n = 5) with chlorpyrifos-cypermethrin poisoning, 18.8% (n = 6) with cypermethrin poisoning, and 3.9% (n = 1) with chlorpyrifos poisoning. Ventilatory requirements were 53.5% (17/32), 42.3% (11/26), and 15.7% (5/32) in Groups 1–3, respectively. Ventilator-free days (Mean ± SD) was significantly lower (p < 0.006) in Group 1 (20.9 ± 9.3 days) than those in Group 2 (26.1 ± 4.4 days) or 3 (27.8 ± 0.6). The median (inter-quartile range) hospital stay was 5.5 (4–19.5), 5 (5–6), and 1 (0.65–1.5) days, respectively, in the three groups. Four patients died in Group 1 (13%). None died in the other groups. Conclusion. Although confounded by the varying quantity of chlorpyrifos and cypermethrin in the different formulations, patients with mixed poisoning appear to have shorter ventilator-free days than patients poisoned by either of the pesticides alone. Further studies are required comparing patients poisoned by formulations with similar quantities of OP and pyrethroid or with analysis of blood pesticide concentration on admission.

Azadirachtin poisoning: a case report

The use of neem-based products is widespread in the Indian Subcontinent. Neem-based pesticides obtained from neem kernels are considered natural and safe. The toxic effects of ingestion and overdose of this pesticide in adults have not been described in this literature. We report the case of a 35-year-old lady who had consumed Azadirachtin in an attempt of deliberate self-harm. The patient had features of neurotoxicity because of Azadirachtin requiring intensive medical care with mechanical ventilation. The patient survived the overdose with no long-lasting side effects of the toxin.

Brain Imaging in Cases with Positive Serology for Dengue with Neurologic Symptoms: A Clinicoradiologic Correlation

BACKGROUND AND PURPOSE: Dengue is a common arboviral disease, which uncommonly involves the brain. There has been a recent surge in dengue cases and dengue-related deaths in tropical countries. The aim of this study was to describe brain imaging findings in patients with dengue infection having neurologic symptoms. MATERIALS AND METHODS: Thirty-five patients with positive serology for dengue with CNS symptoms undergoing imaging of the brain were included in the study. Clinical, laboratory, and imaging parameters were assessed and correlated to poor outcome. RESULTS: A Glasgow Coma Scale score of ≤12 at presentation, clinical classification of severe-type dengue, and the presence of acute renal failure were associated with poor outcome. Imaging parameters associated with poor outcome were involvement of the thalami and cerebellar peduncles and the presence of diffusion restriction and hemorrhagic foci in the brain parenchyma. CONCLUSIONS: Although not specific, dengue infection has imaging findings that can be used to narrow down the differential list and help in prognostication.

Cloxacillin induced agranulocytosis: A rare adverse event of a commonly used antibiotic:

Cloxacillin, a semisynthetic penicillin is a potent inhibitor of most penicillinase-producing Staphylococci. Use of high doses of Cloxacillin for 6 weeks is recommended for the treatment of infective endocarditis caused by methicillin-susceptible Staphylococcus aureus (MSSA). Here, we report a case of Cloxacillin-induced agranulocytosis in a patient treated for MSSA native tricuspid valve endocarditis, which was resolved after discontinuation of the antibiotic. This case report highlights a rare adverse event of a commonly used antibiotic.

Risperidone induced benign intracranial hypertension leading to visual loss

Benign intracranial hypertension (BIH) is a rare but potentially serious condition causing visual loss. Occasionally, medication use has been associated with the occurrence of BIH. We report the case of a 40-year-old obese lady being treated with risperidone for schizophrenia who presented with features of BIH. We report this case, occurring for the 1st time in India, to emphasize that a commonly used atypical antipsychotic drug can rarely cause BIH leading to visual loss.

Spectrum of cardiac manifestations and its relationship to outcomes in patients admitted with scrub typhus infection

AIM To study the spectrum of cardiac manifestations in scrub typhus infection and assess its relationship to outcomes. METHODS Demographic data, electrocardiographic (ECG) changes, left ventricular (LV) systolic and diastolic function, myocardial injury (defined as troponin T > 14 pg/mL), and pericardial effusion were documented. Myocarditis was diagnosed when myocardial injury was associated with global LV systolic dysfunction. The relationship between myocarditis and outcomes was assessed using logistic regression analysis and expressed as odds ratio (OR) with 95%CI. RESULTS The cohort (n = 81; 35 males) aged 49.4 ± 16.1 years (mean, SD) presented 8.1 ± 3.1 d after symptom onset. The APACHE-II score was 15.7 ± 7.0. Forty-eight (59%) patients were ventilated, and 46 (56%) required vasoactive agents. Mortality was 9.9%. ECG changes were non-specific; sinus tachycardia was the most common finding. Myocardial injury was evident in 61.7% of patients and LV systolic dysfunction in 30.9%. A diagnosis of myocarditis was made in 12.3%. In addition, seven patients with regional wall motion abnormalities had LV systolic dysfunction and elevated cardiac enzymes. Mild diastolic dysfunction was observed in 18 (22%) patients. Mild to moderate pericardial effusion was seen in 51%. On multivariate logistic regression analysis, patients with myocarditis tended to be older (OR = 1.04, 95%CI: 0.99-1.09), had shorter symptom duration (OR = 0.69, 95%CI: 0.49-0.98), and tended to stay longer in hospital (OR = 1.17, 95%CI: 0.98-1.40). Myocarditis was not associated with increased mortality. CONCLUSION In scrub typhus infection, cardiac manifestations are frequent and associated with increased morbidity but not mortality.

Risk factors for acquiring scrub typhus among the adults

Background: Behavioral and geographical factors may play a role in the acquisition of scrub typhus infection. In this prospective case–control study, we studied the factors associated with infection. Patients and Methods: Consecutive adult patients admitted with scrub typhus infection over 10 months were recruited. For every case, a geographical control from the same area and a gender-matched clinical control admitted with acute febrile illness were enrolled. The risk factors, which included sanitation, environment, activity, and protective measures, were compared between cases and controls using univariable and multivariable conditional logistic regression analysis and expressed as odds ratio (OR) with 95% confidence interval (CI). Results: The study cohort (n = 225; 132 female) aged 44 ± 17 years comprised of 75 cases and 150 controls from mid to low socioeconomic background. When compared with clinical controls, on univariable conditional regression analysis, cases were more likely to be involved in farming or gardening and less likely to have a toilet within the house. On multivariate regression analysis, only involvement in farming or gardening was associated with infection (OR: 4.2, 95% CI: 1.5–11.5). When compared with geographical controls, on univariable conditional regression analysis, cases were less likely to change undergarments or clothes before sleeping (OR: 3.5, 95% CI: 1.3–9.5) and more likely to have rodents in their house (OR: 2.5, 95% CI: 1–6.4) and rest on grass/mud without a mat (OR: 2.4, 95% CI: 1.1–5.3). On multivariate regression analysis, not changing undergarments or clothes tended to be associated with infection (OR: 2.7, 95% CI: 0.98–7.3). Conclusion: Certain behavioral factors predisposed our cohort to develop scrub typhus infection. Lifestyle changes may reduce the burden of scrub typhus in South India.