Diagnostic value of direct fluorescence antibody staining for detecting Pneumocystis jirovecii in expectorated sputum from patients with HIV infection

Abstract

Direct fluorescent antibody (DFA) staining of induced sputum is frequently used to diagnose Pneumocystis pneumonia (PCP) in patients infected with human immunodeficiency virus, although induction can provoke nausea and bronchospasm. Since the diagnostic value of expectorated sputum examined with DFA stain has not been well evaluated, we reviewed the medical records of HIV-infected patients who were clinically diagnosed as having PCP between 1999 and 2011. Over this 13-year period, we found 76 patients whose records included the results of DFA staining of expectorated sputum and noted that 42 (55.3%) were positive. Polymerase chain reaction to detect Pneumocystis in the sputum of 65 of the patients resulted in the finding of 43 (66.2%) who were positive. Our findings suggest that DFA staining of expectorated sputum could be a useful initial diagnostic method in HIV-infected patients with PCP.

Evaluation of a PCR-electrospray ionization mass spectrometry platform for detection and identification of fungal pathogens directly from prospectively collected bronchoalveolar lavage specimens

“…However, all these patients were immunocompromised patients (Table 3) and all except one had clinical presentations and radiological evidence to support the clinical diagnosis of the disease. AIDS patients often have a high-burden of P. jirovecii, with a previous study showing DFA assay positive rate as high as to 55% (Choe et al, 2014). The detection rate by DFA in this study in the nine clinicalsuspicious-PCP-infection HIV patients was 77.8% (7/9), while by PCR/ ESI-MS was 100% (9/9).…”

“…P. jirovecii remains one of the most common opportunistic pathogens in AIDS patients and occurs in patients with other causes of immunodeficiency (Thomas Jr. and Limper, 2004). The standard reference method for diagnosing P. jirovecii is a direct fluorescence microscopy assay on specimens obtained by BAL (Procop et al, 2004;Choe et al, 2014). There were 7 additional P. jirovecii detections by PCR/ESI-MS that were negative by DFA.…”

Profile of pneumocystis infection in a tertiary care institute in North India

“…In their study, Choe et al . [13] reported 55.3% HIV reactive patients to be positive for PcP by DFA. Earlier studies in the USA showed PcP as the most frequent cause of pulmonary infections (85%) and was also the first cause of hospital admission in HIV patients.…”

Combination of β‐(1, 3)‐D‐glucan testing in serum and qPCR in nasopharyngeal aspirate for facilitated diagnosis of Pneumocystis jirovecii pneumonia

“…Unfortunately, so far, superficial samples have been shown to be less sensitive for the diagnosis of PjP infection, especially because the fungal burden seems too low inside. Thus, May‐Grünwald Giemsa (MGG) or Gomori‐Grocott's methenamine silver (GMS) staining, as well as commercial kits using monoclonal and fluorescent‐conjugated antibodies (IFA, for immunofluorescent assay allowing detection of P jirovecii cysts (asci)), has never provided reliable results: for example, in HIV‐positive patients, only 55.3% sputa were found positive by direct methods during true PjP infection . Eventually, only quantitative real‐time polymerase chain reaction (qPCR) appears to be powerful enough to detect efficiently P jirovecii DNA in upper respiratory samples, but, for technical reasons, is not easily feasible in viscous respiratory specimens like sputa.…”

“…Likewise, its diagnostic performance remains somewhat questionable when considered alone, as it displays real limitations for distinguishing between casual carriage and true infection . Therefore, in upper respiratory samples, qPCR was demonstrated efficient for the microbiological diagnosis in only 48.0% children and in 66.2% HIV‐positive adult patients . It should also be noted that some surrogate biomarkers have been recently developed, such as the measurement of β‐(1,3)‐D‐glucan (BDG) antigen in serum.…”