Epidemiology and risk factors associated with Pneumocystis jirovecii pneumonia in kidney transplant recipients after 6-month trimethoprim-sulfamethoxazole prophylaxis: A case-control study.

BACKGROUND: Pneumocystis jirovecii pneumonia (PCP) is an important cause of morbidity and mortality in kidney transplant recipients (KTRs), and prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) is recommended. The aim of this study was to investigate incidence and risk factors for PCP in KTRs after 6-month TMP-SMX prophylaxis. METHODS: We conducted a case-control study of patients with PCP who received 6-month PCP prophylaxis with TMP-SMX after kidney transplantation (KT). In cases of rejection, PCP prophylaxis was provided for six additional months after anti-rejection therapy. Cytomegalovirus (CMV) infection was not considered an indication for PCP prophylaxis due to concerns of nephrotoxicity associated with TMP-SMX. RESULTS: Among 3941 kidney or pancreas-kidney transplant recipients, 67 (1.7%) developed PCP after discontinuing TMP-SMX. A total of 47 patients with KT PCP and 94 controls were included. Duration of PCP prophylaxis was similar between cases and controls (median 6 months, P = .53). In multivariate analysis, rejection (OR 3.9; 95% CI 1.4-11.1) and CMV infection (OR 2.4; 95% CI 1.0-5.8) were independently associated with PCP development after TMP-SMX. Rejection or CMV infection was observed in 70% of patients with PCP. Time to PCP development after rejection (median [IQR] 6 [5-19] months) was slightly shorter than after CMV infection (median [IQR] 9 [5-12] months; P = .18). CONCLUSION: Post-prophylaxis PCP occurred in <2% of KTRs, and about two-thirds of these experienced rejection or CMV infection. These data suggest that at least 6 to 9-month additional chemoprophylaxis may be needed to prevent PCP in KTRs with transplant rejection or CMV infection.

Sensitivity of the Cytomegalovirus Antigenemia Assay to Diagnose Cytomegalovirus Retinitis.

BACKGROUND: Cytomegalovirus (CMV) retinitis is one of the most important tissue-invasive CMV diseases in immunocompromised patients. Since 1980, non-invasive diagnostic methods, notably the CMV antigenemia assay, have been widely used as adjunct tests to diagnose tissue-invasive CMV diseases. However, there are limited data on the diagnostic value of the CMV antigenemia assay for diagnosing CMV retinitis. MATERIALS AND METHODS: We performed a retrospective review of all cases of CMV retinitis at Asan Medical Center, Seoul, South Korea over a 9-year period. The diagnosis of CMV retinitis was made by experienced ophthalmologists according to medical history and an ophthalmoscopic appearance of typical retinopathy, together with absence of an alternative diagnosis. RESULTS: We analyzed 44 patients with CMV retinitis (affecting 57 eyes) for whom the CMV antigenemia assay was performed. Of the 44 patients, 31 (70%) were HIV-uninfected and 13 (30%) were HIV-infected. The overall sensitivity of the CMV antigenemia assay was 66% (95% confidence interval [CI] 50-80%). The test's sensitivity showed a non-significant trend towards being higher in HIV-infected patients than in HIV-uninfected patients (sensitivity 85% vs 58%, respectively, P = 0.16). In a subgroup analysis of the 35 patients without other concurrent tissue-invasive CMV disease, the sensitivity of the CMV antigenemia assay was 57% (95% CI 40-74%). CONCLUSIONS: The CMV antigenemia assay has limited value as a non-invasive diagnostic adjunct test for CMV retinitis. Therefore, the results of the assay need to be interpreted in the context of underlying disease, clinical presentation, and ophthalmoscopic findings.

Diagnostic performance of T-SPOT.TB for extrapulmonary tuberculosis according to the site of infection.

BACKGROUND: The clinical manifestations of extrapulmonary tuberculosis (E-TB) vary according to site of disease, so we tested the hypothesis that IFN-γ producing T-cell responses also vary in parallel. Therefore we conducted a prospective, blinded, observational study to evaluate the diagnostic performance of blood T-SPOT.TB according to the various sites of E-TB. METHODS: From April 2008 to August 2010, all patients with suspected E-TB were enrolled at a tertiary hospital in an intermediate TB-burden country. Final diagnosis in patients with suspected E-TB was classified by clinical category. RESULTS: A total of 368 patients with suspected E-TB were enrolled; 196 (53%) were classified as having TB, including 119 (32%) with confirmed TB, 34 (9%) probable TB, and 43 (12%) possible TB; the remaining 172 (47%) were classified as not having TB. After excluding patients with possible TB, the T-SPOT.TB was more sensitive in patients with chronic forms of E-TB such as lymph node or osteoarticular TB (93%, 95% CI 83%-97%) than in patients with acute forms of E-TB such as TB meningitis or miliary TB (79%, 95% CI 66%-87%, P = 0.03). CONCLUSIONS: The diagnostic performance of the blood T-SPOT.TB differs among patients with various clinical manifestations of E-TB.