Serum cryptococcal antigen titre as a diagnostic tool and a predictor of mortality in HIV‐infected patients with cryptococcal meningitis

• Published in: HIV medicine Vol. 20; no. 1; pp. 69 - 73
• Main Authors: Chen, J, Zhang, R, Shen, Y, Liu, L, Qi, T, Wang, Z, Mehraj, V, Routy, JP, Lu, H
• Format: Journal Article
• Language: English
• Published: England Wiley Subscription Services, Inc 01.01.2019
• Subjects: Adult; Agglutination; AIDS; Antifungal Agents - therapeutic use; Antigens; Antigens, Fungal - blood; Coma; Confidence intervals; cryptococcal antigen; cryptococcal meningitis; Cryptococcus neoformans - immunology; Diagnosis; Diagnostic software; Diagnostic systems; Female; Fungicides; Headache; HIV; HIV Infections - immunology; HIV Infections - microbiology; HIV Infections - mortality; Human immunodeficiency virus; Humans; Latex; Latex agglutination; Male; Meningitis; Meningitis, Cryptococcal - blood; Meningitis, Cryptococcal - diagnosis; Meningitis, Cryptococcal - drug therapy; Meningitis, Cryptococcal - mortality; Middle Aged; Mortality; Patients; Public health; Retrospective Studies; Sensitivity and Specificity; Spinal Puncture; mortality; AIDS; cryptococcal antigen; HIV; cryptococcal meningitis
• ISSN: 1464-2662; 1468-1293
• DOI: 10.1111/hiv.12679

Objectives The aim was to determine the effectiveness of the serum cryptococcal antigen (CrAg) test in the diagnosis of concurrent cryptococcal meningitis (CM) and as a predictor of mortality in HIV‐infected patients. Methods In this retrospective study, all HIV‐infected patients admitted to Shanghai Public Health Clinical Center from 1 January 2014 to 31 August 2016 were screened for serum CrAg using the latex agglutination test. Serum CrAg‐positive patients underwent lumbar puncture to confirm CM prior to the initiation of appropriate antifungal therapy and were followed up for at least 6 months. Results One hundred and four (7.1%) of the total of 1474 HIV‐infected patients screened were serum CrAg‐positive. CM was diagnosed in the majority of serum CrAg‐positive patients (71.3%; 67 of 94) and was confirmed in all (46 of 46) of the patients with headache or coma and in 43.8% (21 of 48) of patients without neurological symptoms. CrAg titres ≥ 1:1024 showed a sensitivity of 82.5% and a specificity of 86.7% for the diagnosis of concurrent CM (P < 0.001). The positive predictive value for CM in this population was 94.3%. A total of 13 serum CrAg‐positive patients [13.8%; 95% confidence interval (CI) 7.5–22.4%] died (11 as a result of CM and two others as a result of bacterial pneumonia) despite early antifungal treatment initiation. Serum CrAg titres ≥ 1:1024 predicted all‐cause mortality (hazard ratio 3.69; P = 0.03). Conclusions Serum CrAg titres ≥ 1:1024 not only were associated with concurrent CM but also predicted mortality. HIV‐infected patients with a positive serum CrAg test during screening should receive lumbar punctures regardless of symptoms to rule out CM and patients with serum CrAg titres ≥ 1:1024 should be offered immediate care.