A Multicenter Case-control Study of the Effect of Acute Rejection and Cytomegalovirus Infection on Pneumocystis Pneumonia in Solid Organ Transplant Recipients.

BACKGROUND: Pneumocystis pneumonia (PCP) is associated with morbidity and mortality in solid organ transplant (SOT) recipients. In this case-control study, we determined the association between posttransplant PCP and 3 variables: cytomegalovirus (CMV) infection, allograft rejection, and prophylaxis. METHODS: Eight transplant centers participated. For each case (SOT recipient with PCP), 3-5 controls (SOT recipients without PCP) were included. Controls were matched to the cases based on transplant center, type of allograft, and date of transplantation (±6 months). RESULTS: We enrolled 53 cases and 209 controls. Transplant types included kidney (n = 198), heart (n = 30), liver (n = 15), kidney-pancreas (n = 14), and lung (n = 5). PCP occurred beyond 12 months after transplantation in 43 (81.1%) cases. Thirty-four cases (64.1%) required admission to the intensive care unit, and 28 (52.8%) had mechanical ventilation. Allograft failure occurred in 20 (37.7%) cases, and 14 (26.9%) died. No patient developed PCP prophylaxis breakthrough. The proportion of female sex (P = .009), kidney dysfunction (P = .001), cardiac diseases (P = .005), diabetes mellitus (P = .03), allograft rejection (P = .001), CMV infection (P = .001), and severe lymphopenia (P = .001) were significantly higher in cases. In the logistic regression model, CMV infection (adjusted odds ratio [aOR], 4.6 [95% confidence interval {CI}, 2.0-10.5]) and allograft rejection (aOR, 3.0 [95% CI, 1.5-6.1]) significantly increased the likelihood of PCP. CONCLUSIONS: PCP was mostly a late-onset disease occurring after complete course of prophylaxis, particularly among patients with CMV infection or allograft rejection. PCP is associated with significant allograft loss. Extended prophylaxis targeting recipients with allograft rejection or CMV infection may reduce the risk of PCP.

Serious fungal infections in Canada.

There are currently no nationwide epidemiological data on fungal infections in Canada. We estimated the burden of serious fungal diseases using literature review and modeling, as per a methodology previously described by the LIFE program ( http://www.LIFE-worldwide.org ). Among the population of Canada (35.5 million in 2014), it was estimated that approximately 1.8% are affected by a serious fungal infection. Recurrent vulvovaginal candidiasis, severe asthma with fungal sensitization, and allergic bronchopulmonary aspergillosis are the most frequent infections, with population prevalences of 498,688 (1403/100,000), 73,344 (206/100,000), and 61,854 (174/100,000) cases, respectively. Over 3000 invasive fungal infections are estimated to occur annually, with incidences of 2068 cases (5.8/100,000) of invasive candidiasis, 566 cases (1.6/100,000) of invasive aspergillosis, 252 cases (0.71/100,000) of Pneumocystis pneumonia, 99 cases (0.28/100,000) of endemic mycoses, and 63 cases (0.18/100,000) of cryptococcosis. These estimates warrant validation through more formal epidemiological studies in Canada.

Histoplasmosis and subcutaneous nodules in a kidney transplant recipient: erythema nodosum versus fungal panniculitis.

Erythema nodosum (EN)-like lesions are a rare occurrence after solid organ transplantation. Differential diagnosis includes infective panniculitis, which can be a feature of progressive disseminated histoplasmosis (PDH), an uncommon but severe form affecting primarily immunocompromised hosts. We report on a fatal case of PDH, which presented as fungal panniculitis masquerading as EN in a renal allograft recipient 25 years after transplantation. We discuss the clinical, histopathological, and microbiological characteristics of this rare complication, with focus on its distinction from EN. This case emphasizes the central role of biopsy in transplant recipients presenting with cutaneous lesions, and the importance of clinicopathologic correlation and complementary microbiological investigations.

Sporadic Legionnaires' disease: the role of domestic electric hot-water tanks.

Sporadic community-acquired legionellosis (SCAL) can be acquired through contaminated aerosols from residential potable water. Electricity-dependent hot-water tanks are widely used in the province of Quebec (Canada) and have been shown to be frequently contaminated with Legionella spp. We prospectively investigated the homes of culture-proven SCAL patients from Quebec in order to establish the proportion of patients whose domestic potable hot-water system was contaminated with the same Legionella isolate that caused their pneumonia. Water samples were collected in each patient's home. Environmental and clinical isolates were compared using pulsed-field gel electrophoresis. Thirty-six patients were enrolled into the study. Legionella was recovered in 12/36 (33%) homes. The residential and clinical isolates were found to be microbiologically related in 5/36 (14%) patients. Contaminated electricity-heated domestic hot-water systems contribute to the acquisition of SCAL. The proportion is similar to previous reports, but may be underestimated.