LAUSR

To the editor: Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by mutations in genes encoding NADPH oxidase complex protein subunits, which leads to skin and soft tissue infection, pneumonia, abscesses, and granulomatous inflammation all of which could be life-threatening [1]. Prophylactic antimicrobials are the mainstay of treatment for CGD. Some of these antimicrobials are nephrotoxic and may lead to end-stage renal disease (ESRD) [2]. The aim of our study was to assess the prevalence of ESRD in CGD patients using the USIDNET registry. We queried the USIDNET database on 28 March 2017 requesting demographic data on CGD patients, number of CGD patients who required renal replacement therapy (hemodialysis and transplant) and timeline to renal replacement therapy from CGD diagnosis. A second query on 02 May 2017 requested all antimicrobials (drug, indication, dose, outcome, complications) received by patients identified in the first query to have had a diagnosis of medical renal disease. Queries of a case inclusion were resolved by consensus between the two authors. Five hundred sixteen patients with CGD were entered in the database of which 435 (84.3%) were male (Table 1). Twelve patients were Caucasian while two were of AfricanAmerican descent. Median age of CGD diagnosis was 3.55 years (IQR 0.7–13.25). Renal disease was identified in 14 patients (2.7%), with equal gender distribution. Ten patients had a diagnosis of BRenal Failure,^ 2 patients had chronic kidney disease, 1 patient had acute kidney injury, 1 patient had non-specific ‘kidney disease’. Etiology for renal failure was identified in 2 patients (glomerulonephritis and polycystic kidneys). Pneumonia with lung abscesses was the most common documented infection in this cohort (9 patients). Genitourinary infection was documented in 2 patients (pyelonephritis and urinary tract infection). Patients 2 and 12 received amphotericin B; however, no diagnosis of aspergillosis was documented. Patient 1 was documented to have BFungal infection of central nervous system^ while patient 4 had Bfungal infection of lung^. No other fungal infections were documented. X-linked CGD with CYBB gene mutation was present in 11 of 343 patients with the mutation (3.2%). Three patients had autosomal recessive CGD with NCF1 mutation (of a total 18 patients with the mutation). Walther et al. described a cohort of CGD patients with renal manifestations. Seven of 60 (11.7%) patients had decreased renal function while 3 patients had bladder granulomas [3]. Nephrotoxic antimicrobials (particularly amphotericin) are thought to be the main etiologic agent for chronic kidney disease in CGD [4]. We attempted to cross reference fungal infection as a surrogate for amphotericin use; however, only 2 patients were documented to have such a diagnosis (patients 1 and 4). Chronic urinary tract infections can also contribute to ESRD [5]. Renal replacement therapy has been shown to be successful in patients with CGD [2]. This is the first report using the USIDNET registry data on the prevalence of ESRD in CGD patients. This retrospective dataset review has many limitations including the inability to measure temporality of onset of renal disease from diagnosis of CGD. Further there were no formal standard coding renal diagnoses. This dataset was not sufficient to enable assessing the relationship between antimicrobial prescription and * Keith A. Sacco [email protected]