Clinical and laboratory predictors of Lassa fever outcome in a dedicated treatment facility in Nigeria: a retrospective, observational cohort study.

BACKGROUND: Lassa fever is a viral haemorrhagic disease endemic to west Africa. No large-scale studies exist from Nigeria, where the Lassa virus (LASV) is most diverse. LASV diversity, coupled with host genetic and environmental factors, might cause differences in disease pathophysiology. Small-scale studies in Nigeria suggest that acute kidney injury is an important clinical feature and might be a determinant of survival. We aimed to establish the demographic, clinical, and laboratory factors associated with mortality in Nigerian patients with Lassa fever, and hypothesised that LASV was the direct cause of intrinsic renal damage for a subset of the patients with Lassa fever. METHODS: We did a retrospective, observational cohort study of consecutive patients in Nigeria with Lassa fever, who tested positive for LASV with RT-PCR, and were treated in Irrua Specialist Teaching Hospital. We did univariate and multivariate statistical analyses, including logistic regression, of all demographic, clinical, and laboratory variables available at presentation to identify the factors associated with patient mortality. FINDINGS: Of 291 patients treated in Irrua Specialist Teaching Hospital between Jan 3, 2011, and Dec 11, 2015, 284 (98%) had known outcomes (died or survived) and seven (2%) were discharged against medical advice. Overall case-fatality rate was 24% (68 of 284 patients), with a 1·4 times increase in mortality risk for each 10 years of age (p=0·00017), reaching 39% (22 of 57) for patients older than 50 years. Of 284 patients, 81 (28%) had acute kidney injury and 104 (37%) had CNS manifestations and thus both were considered important complications of acute Lassa fever in Nigeria. Acute kidney injury was strongly associated with poor outcome (case-fatality rate of 60% [49 of 81 patients]; odds ratio [OR] 15, p<0·00001). Compared with patients without acute kidney injury, those with acute kidney injury had higher incidence of proteinuria (32 [82%] of 39 patients) and haematuria (29 [76%] of 38) and higher mean serum potassium (4·63 [SD 1·04] mmol/L) and lower blood urea nitrogen to creatinine ratio (8·6 for patients without clinical history of fluid loss), suggesting intrinsic renal damage. Normalisation of creatinine concentration was associated with recovery. Elevated serum creatinine (OR 1·3; p=0·046), aspartate aminotransferase (OR 1·5; p=0·075), and potassium (OR 3·6; p=0·0024) were independent predictors of death. INTERPRETATION: Our study presents detailed clinical and laboratory data for Nigerian patients with Lassa fever and provides strong evidence for intrinsic renal dysfunction in acute Lassa fever. Early recognition and treatment of acute kidney injury might significantly reduce mortality. FUNDING: German Research Foundation, German Center for Infection Research, Howard Hughes Medical Institute, US National Institutes of Health, and World Bank.

Renal sonographic parameters in human immunodeficiency virus - infected subjects and relationship to CD4 cell count.

Nephropathy in human immunodeficiency virus (HIV)-infected patient is common and constitutes a major cause of endstage kidney disease. CD4 cell count is a useful parameter in the assessment of the degree of immunosuppression among HIV-infected patients. Manifestations of renal disease are thought to be more profound when CD4 cell counts are low. Sonography is a safe and inexpensive method of evaluating renal disease, including renal sizes and degree of echogenicity. Ultrasound examination was carried out prospectively at the University of Benin Teaching Hospital on 120 HIV-infected patients comprising 45 males (37.5%) and 75 females (63.5%). Renal sizes and degree of echogenicity were assessed. Correlation with CD4 + cell counts of the patients was done. Mean CD4 cell count mean was 18.34 ± 142.18 cells/mm 3 with female patients having a significantly higher cell count compared with males. Seventy-four patients (63.8%) had a cell count of <200 cells/mm 3 . Renal sizes were normal in 85%, small in 7%, and large in 8% of patients. Fifty patients (41.7%) had increased renal echogenicity and 8 (6.7%) had severe increased echo-texture. CD4 cell count did not correlate with renal sizes and echotexture. Results of this study show that large kidneys and marked increase in renal echotexture were not common even in a population of patients where the majority had CD4 cell count < 200 cells/mm 3 . This study shows that increased renal sizes and degree of echogenicity alone are not useful predictors of renal involvement in HIV/AIDS.