Development of a case fatality prognostic score for HIV-associated histoplasmosis

Abstract

Objectives: The burden of histoplasmosis is as great as that of tuberculosis in Latin America and the attributable mortality is even higher. A better assessment of severity could help reduce mortality. Methods: From the French Guiana HIV-histoplasmosis database, we attempted to identify factors associated with 30-day death after antifungal drug initiation and constructed a prognostic score. We evaluated its discrimination performance using several resampling methods. Results: Of the 415 patients included, 56 (13.5%) died within 30 days of treatment. The fatality-associated factors were performance status ≥3, altered mental status, dyspnea, C-reactive protein ≥75 mg/l, hemoglobin <9 g/dl and/or a platelet <100000/ml, and an interstitial lung pattern on chest X-ray. We constructed a 12-point prognostic score. A threshold ≥5 classified patients as alive or dead at 30 days with a sensitivity of 84%, a specificity of 81%, a positive predicted value of 40%, and a negative predicted value of 97%. The area under the curve of the receiver operating characteristic curves from the different resamples were stable between 0.88 and 0.93. Conclusion: The histoplasmosis case fatality score, which is easy and inexpensive to perform, is a good tool for assessing severity and helping in the choice of induction therapy. An external validation remains necessary to generalize these results.

Keywords

• Histoplasmosis
• Histoplasma capsulatum
• HIV
• Prognosis