The prevalence of laboratory-confirmed Pneumocystis jirovecii in HIV-infected adults in Africa: A systematic review and meta-analysis.

BACKGROUND: The epidemiology of Pneumocystis jirovecii, known to colonize the respiratory tract and cause a life-threatening HIV-associated pneumonia (PCP), is poorly described in Africa. We conducted a systematic review to evaluate P. jirovecii prevalence in African HIV-positive adults with or without respiratory symptoms. METHODS: We searched Medline, Embase, Cochrane library, Africa-Wide, and Web of Science for studies employing PCR and/or microscopy for P. jirovecii detection in respiratory samples from HIV-positive adults in Africa between 1995 and 2020. Prevalence with respiratory symptoms was pooled using random-effect meta-analysis, and stratified by laboratory method, sample tested, study setting, CD4 count, and trimethoprim/sulfamethoxazole prophylaxis. Colonization prevalence in asymptomatic adults and in adults with non-PCP respiratory disease was described, and quantitative PCR (qPCR) thresholds to distinguish colonization from microscopy-confirmed PCP reviewed. RESULTS: Thirty-two studies were included, with 27 studies (87%) at high risk of selection bias. P. jirovecii was detected in 19% [95% confidence interval (CI): 12-27%] of 3583 symptomatic and in 9% [95% CI: 0-45%] of 140 asymptomatic adults. Among symptomatic adults, prevalence was 22% [95% CI: 12-35%] by PCR and 15% [95% CI: 9-23%] by microscopy. Seven percent of 435 symptomatic adults had PCR-detected Pneumocystis colonization without evidence of PCP [95% CI: 5-10%, four studies]. One study established a qPCR cutoff of 78 copies/5µl of DNA in 305 induced sputum samples to distinguish Pneumocystis colonization from microscopy-confirmed PCP. CONCLUSION: Despite widened access to HIV services, P. jirovecii remains common in Africa. Prevalence estimates and qPCR-based definitions of colonization are limited, and overall quality of studies is low.

(1→3)-ß-D-glucan testing for the detection of invasive fungal infections in immunocompromised or critically ill people.

BACKGROUND: Invasive fungal infections (IFIs) are life-threatening opportunistic infections that occur in immunocompromised or critically ill people. Early detection and treatment of IFIs is essential to reduce morbidity and mortality in these populations. (1→3)-ß-D-glucan (BDG) is a component of the fungal cell wall that can be detected in the serum of infected individuals. The serum BDG test is a way to quickly detect these infections and initiate treatment before they become life-threatening. Five different versions of the BDG test are commercially available: Fungitell, Glucatell, Wako, Fungitec-G, and Dynamiker Fungus. OBJECTIVES: To compare the diagnostic accuracy of commercially available tests for serum BDG to detect selected invasive fungal infections (IFIs) among immunocompromised or critically ill people. SEARCH METHODS: We searched MEDLINE (via Ovid) and Embase (via Ovid) up to 26 June 2019. We used SCOPUS to perform a forward and backward citation search of relevant articles. We placed no restriction on language or study design. SELECTION CRITERIA: We included all references published on or after 1995, which is when the first commercial BDG assays became available. We considered published, peer-reviewed studies on the diagnostic test accuracy of BDG for diagnosis of fungal infections in immunocompromised people or people in intensive care that used the European Organization for Research and Treatment of Cancer (EORTC) criteria or equivalent as a reference standard. We considered all study designs (case-control, prospective consecutive cohort, and retrospective cohort studies). We excluded case studies and studies with fewer than ten participants. We also excluded animal and laboratory studies. We excluded meeting abstracts because they provided insufficient information. DATA COLLECTION AND ANALYSIS: We followed the standard procedures outlined in the Cochrane Handbook for Diagnostic Test Accuracy Reviews. Two review authors independently screened studies, extracted data, and performed a quality assessment for each study. For each study, we created a 2 × 2 matrix and calculated sensitivity and specificity, as well as a 95% confidence interval (CI). We evaluated the quality of included studies using the Quality Assessment of Studies of Diagnostic Accuracy-Revised (QUADAS-2). We were unable to perform a meta-analysis due to considerable variation between studies, with the exception of Candida, so we have provided descriptive statistics such as receiver operating characteristics (ROCs) and forest plots by test brand to show variation in study results. MAIN RESULTS: We included in the review 49 studies with a total of 6244 participants. About half of these studies (24/49; 49%) were conducted with people who had cancer or hematologic malignancies. Most studies (36/49; 73%) focused on the Fungitell BDG test. This was followed by Glucatell (5 studies; 10%), Wako (3 studies; 6%), Fungitec-G (3 studies; 6%), and Dynamiker (2 studies; 4%). About three-quarters of studies (79%) utilized either a prospective or a retrospective consecutive study design; the remainder used a case-control design. Based on the manufacturer's recommended cut-off levels for the Fungitell test, sensitivity ranged from 27% to 100%, and specificity from 0% to 100%. For the Glucatell assay, sensitivity ranged from 50% to 92%, and specificity ranged from 41% to 94%. Limited studies have used the Dynamiker, Wako, and Fungitec-G assays, but individual sensitivities and specificities ranged from 50% to 88%, and from 60% to 100%, respectively. Results show considerable differences between studies, even by manufacturer, which prevented a formal meta-analysis. Most studies (32/49; 65%) had no reported high risk of bias in any of the QUADAS-2 domains. The QUADAS-2 domains that had higher risk of bias included participant selection and flow and timing. AUTHORS' CONCLUSIONS: We noted considerable heterogeneity between studies, and these differences precluded a formal meta-analysis. Because of wide variation in the results, it is not possible to estimate the diagnostic accuracy of the BDG test in specific settings. Future studies estimating the accuracy of BDG tests should be linked to the way the test is used in clinical practice and should clearly describe the sampling protocol and the relationship of time of testing to time of diagnosis.

Genotyping of Pneumocystis jirovecii by Use of a New Simplified Nomenclature System Based on the Internal Transcribed Spacer Regions and 5.8S rRNA Gene of the rRNA Operon.

Genotyping based on internal transcribed spacer 1 (ITS1) and ITS2 of the rRNA operon has played an important role in understanding the transmission and epidemiology of Pneumocystis jirovecii, one of the major opportunistic pathogens in individuals with AIDS and other immunocompromised individuals. The widespread use of this typing system has resulted in several problems, including inconsistent genotype nomenclatures, difficult data transferability, and complicated interpretation of the length variation in multiple homopolymeric tracts. The aim of this study was to establish a new, simplified genotype nomenclature system for P. jirovecii based on the ITS1 and ITS2 sequences. We first analyzed the complete ITS1, 5.8S rRNA gene, and ITS2 sequences (termed ITS1-5.8S-ITS2) in 27 recent P. jirovecii isolates from China and identified 18 unique genotypes. Subsequently, we performed a comprehensive classification of more than 400 ITS1- and ITS2-related sequences from GenBank and an in-depth evaluation of the length variation of multiple homopolymeric tracts within ITS1-5.8S-ITS2. Integration of the results from these analyses led to a new, simplified genotype nomenclature system including 62 unique ITS1-5.8S-ITS2 genotypes, simply designated types 1 through 62. This new system offers several advantages over traditional ITS1- and ITS2-based typing systems, including a simpler analysis and interpretation process, a higher discriminative power, and no limitation in assigning potential new genotypes. This new system is expected to facilitate the standardization of P. jirovecii genotyping and easy data exchanges across different laboratories.

Pneumocystis jiroveci in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of Pneumocystis jiroveci fungal infection transplant recipients. Pneumonia (PJP) may develop via airborne transmission or reactivation of prior infection. Nosocomial clusters of infection have been described among transplant recipients. PJP should not occur during prophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX). Without prophylaxis, PJP risk is greatest in the first 6 months after organ transplantation but may develop later. Risk factors include low lymphocyte counts, cytomegalovirus infection (CMV), hypogammaglobulinemia, treated graft rejection or corticosteroids, and advancing patient age (>65). Presentation typically includes fever, dyspnea with hypoxemia, and cough. Chest radiographic patterns generally reveal diffuse interstitial processes best seen by CT scans. Patients generally have PO2  < 60 mm Hg, elevated serum lactic dehydrogenase (LDH), and elevated serum (1 â†’ 3) ß-d-glucan assay. Specific diagnosis uses respiratory specimens with direct immunofluorescent staining; invasive procedures may be required. Quantitative PCR is a useful adjunct to diagnosis. TMP-SMX is the drug of choice for therapy; drug allergy should be documented before resorting to alternative therapies. Adjunctive corticosteroids may be useful early. Routine PJP prophylaxis is recommended for at least 6-12 months post-transplant, preferably with TMP-SMX.

Urinary tract infections in renal transplant recipients at a quaternary care centre in Australia.

BACKGROUND: Urinary tract infections (UTI) are the most common of infections after renal transplantation. The consequences of UTIs in this population are serious, with increased morbidity and hospitalisation rates as well as acute allograft dysfunction. UTIs may impair overall graft and patient survival. We aimed to identify the prevalence and risk factors for post-transplant UTIs and assess UTIs' effect on renal function during a UTI episode and if they result in declining allograft function at 2 years post-transplant. Additionally, the causative organism, the class of antibacterial drug employed for each UTI episode and utilisation rates of trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were also quantified. METHODS: This was a retrospective study of 72 renal transplant patients over a 5-year period who were managed at the Royal Brisbane and Women's Hospital. Patient charts, pathology records and dispensing histories were reviewed as part of this study and all UTIs from 2 years post transplantation were captured. RESULTS: Of these patients, 20 (27.8%) had at least one UTI. Older age (p = 0.015), female gender (p < 0.001), hyperglycaemia (p = 0.037) and acute rejection episodes (p = 0.046) were risk factors for developing a UTI on unadjusted analysis. Female gender (OR 4.93) and age (OR 1.03) were statistically significant risk factors for a UTI on adjusted analysis. On average, there was a 14.4% (SEM 5.20) increase in serum creatinine during a UTI episode, which was statistically significant (p = 0.027), and a 9.1% (SEM 6.23) reduction in serum creatinine after the UTI episode trending toward statistical significance. (p = 0.076). Common organisms (Escherichia coli and Klebsiella pneumoniae) accounted for 82% of UTI episodes with 70% of UTI cases requiring only a single course of antibiotic treatment. Furthermore, the antibiotic class used was either a penicillin (49%) or cephalosporin (36%) in the majority of UTIs. The use of TMP/SMX prophylaxis for Pneumocystis carinii pneumonia prophylaxis did not influence the rate of UTI, with > 90% of the cohort using this treatment. CONCLUSIONS: There was no significant change in serum creatinine and estimated glomerular filtrate rate from baseline to 2 years post-transplant between those with and without a UTI.

[Pneumocystis jirovecii pneumonia-an opportunistic infection undergoing change]. / Pneumocystis-jirovecii-Pneumonie ­ eine opportunistische Infektion im Wandel.

Pneumocystis jirovecii pneumonia (PcP) has for many years been reported mostly in human immunodeficiency virus-infected patients. Increasingly, it also affects other immunocompromised patients, e.g. after organ or allogeneic stem cell/bone marrow transplantation, patients with hematologic malignancies or autoimmune diseases. The diagnosis of PcP relies on a critical evaluation of clinical symptoms, risk factors, radiologic features and microbiological tests. High dose cotrimoxazole is the most effective therapeutic option. Rapid initiation is essential, since mortality is especially high in patients admitted to intensive care with respiratory failure. This article reviews the current epidemiology of PcP and highlights the diagnostic and therapeutic options. Recommendations for primary and secondary prophylaxis are summarized.

Reliable differentiation of Pneumocystis pneumonia from Pneumocystis colonisation by quantification of Major Surface Glycoprotein gene using real-time polymerase chain reaction.

A clear differentiation between pneumonia due to Pneumocystis jirovecii and "colonisation" is required for optimal case management. A quantification of fungal burden using major surface glycoprotein (MSG) gene-based real-time PCR was undertaken for the same. Lower respiratory tract samples collected from 104 patients of clinically suspected Pneumocystis pneumonia (PCP) were subjected to quantitative PCR using MSG gene. Based on whether or not the cases were treated for PCP, the efficacy of qPCR to differentiate between "diseased" and "colonised" was evaluated. Standard curve of plasmid-cloned gene and receiver operating characteristic curve defined a cut-off of Ct ≤ 25 to diagnose PCP and Ct within 26-39.3 range to depict colonisation. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the qPCR was 100%, each for diagnosing PCP. MSG-gene-based qPCR is a robust tool for the reliable differentiation of Pneumocystis pneumonia from colonisation.

[Extrapulmonary pneumocystosis: a case report]. / Neumocistosis extrapulmonar: comunicación de un caso.

We report a case of a middle-age male patient, with newly HIV infection in AIDS stage diagnosis, no comorbitidies, who was hospitalized for subacute malaise, fever, self-limited unproductive cough and no bloody chronic diarrea. The diagnosis of Pneumocystis jiroveci pneumonia was performed by imagenological suspicion and stains of cysts of this pathogen with bronchoalveolar lavage samples. Treatment was initiated with oral cotrimoxazole and starting HAART with good clinical outcome. Concomitantly, an etiologic study was conducted for chronic diarrhea and through histopathological examination of colonic mucosa, numerous extracellular cystic structures Pneumocystis characteristics were observed, performing the diagnosis of extrapulmonary pneumocystosis. Extrapulmonary pneumocystosis is a rare cause of P. jiroveci infection, requires a high index of suspicion and should be approached in HIV patients with severe AIDS which is common in co-infection of various infections and is peremptory to make an etiologic diagnosis and early treatment.

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

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.

An improved single-round PCR leads to rapid and highly sensitive detection of Pneumocystis spp.

In order to standardize a polymerase chain reaction (PCR)-based method of Pneumocystis detection, we describe the development of an improved PCR method that targets the Pneumocystis mtLSUrRNA gene. Design of a new primer pair and PCR program with suitable parameters and optimization resulted in a simpler and faster single-round amplification assay. The sensitivity of the novel Pneumocystis genus-specific PCR proved comparable to the reference nested PCR. The improvement that this new PCR assay offers in the detection and epidemiological studies of Pneumocystis spp. infection in research laboratories is discussed.

Development and evaluation of a real-time PCR assay for detection of Pneumocystis jirovecii on the fully automated BD MAX platform.

Pneumocystis jirovecii is an opportunistic pathogen in immunocompromised and AIDS patients. Detection by quantitative PCR is faster and more sensitive than microscopic diagnosis yet requires specific infrastructure. We adapted a real-time PCR amplifying the major surface glycoprotein (MSG) target from Pneumocystis jirovecii for use on the new BD MAX platform. The assay allowed fully automated DNA extraction and multiplex real-time PCR. The BD MAX assay was evaluated against manual DNA extraction and conventional real-time PCR. The BD MAX was used in the research mode running a multiplex PCR (MSG, internal control, and sample process control). The assay had a detection limit of 10 copies of an MSG-encoding plasmid per PCR that equated to 500 copies/ml in respiratory specimens. We observed accurate quantification of MSG targets over a 7- to 8-log range. Prealiquoting and sealing of the complete PCR reagents in conical tubes allowed easy and convenient handling of the BD MAX PCR. In a retrospective analysis of 54 positive samples, the BD MAX assay showed good quantitative correlation with the reference PCR method (R(2) = 0.82). Cross-contamination was not observed. Prospectively, 278 respiratory samples were analyzed by both molecular assays. The positivity rate overall was 18.3%. The BD MAX assay identified 46 positive samples, compared to 40 by the reference PCR. The BD MAX assay required liquefaction of highly viscous samples with dithiothreitol as the only manual step, thus offering advantages for timely availability of molecular-based detection assays.

Serum (1->3)-beta-D-glucan levels in primary infection and pulmonary colonization with Pneumocystis jirovecii.

This article describes positive (1 → 3)-ß-D-glucan levels in serum from infants with primary Pneumocystis infection and from immunosuppressed patients with Pneumocystis pneumonia (PCP) and negative levels in serum from patients colonized by Pneumocystis jirovecii. Glucan detection is a complementary tool for the diagnosis of the diverse clinical presentations of P. jirovecii infection.

Quantitative Pneumocystis jirovecii real-time PCR to differentiate disease from colonisation.

We studied a Pneumocystis jirovecii quantitative polymerase chain reaction (qPCR) for distinguishing P. jirovecii disease from colonisation. Eighty-two respiratory samples from 65 patients with qPCR results were analysed against a gold standard clinical diagnosis of Pneumocystis pneumonia. High inter-assay reproducibility using recombinant and clinical material was observed. Contemporaneous samples from the same patient displayed high variability (median difference 2.6 log10 copies/mL, IQR 2.1-3.1 log10 copies/mL). Despite this, area under the receiver operator characteristic curve was 0.8. An optimum cut-off of 2.8 log10 copies/mL (equivalent to CT of 34.0 cycles) had 59% sensitivity and 92% specificity. The median P. jirovecii load was 7.3 log10 copies/mL in HIV patients compared to 2.6 log10 copies/mL in non-HIV patients. Specificity was 100% in non-HIV patients with qPCR of >3.8 log10 copies/mL. qPCR was useful for distinguishing P. jirovecii disease from colonisation. A quantitative standard, standardisation of definitions and methods are required to improve the generalisability of results.

Evaluation of sensitivity of multiplex PCR for Detection of Mycobacterium tuberculosis and Pneumocystis jirovecii in clinical samples.

A multiplex PCR assay for the simultaneous detection of Mycobacterium tuberculosis and Pneumocystis jirovecii was developed using IS6110-based detection for M. tuberculosis and mitochondrial large-subunit (mtLSU) rRNA gene detection for P. jirovecii. Ninety-five pulmonary blinded samples were examined using the developed multiplex PCR assay, and the results were compared with those obtained by the single nested PCRs targeting IS6110 for M. tuberculosis and mtLSU rRNA for P. jirovecii. Of the 95 pulmonary samples tested, the multiplex nested PCR developed here could detect 36 cases of M. tuberculosis infection, 35 cases of P. jirovecii infection, and 17 cases of M. tuberculosis and P. jirovecii coinfections. The sensitivities of the multiplex nested PCR in detecting M. tuberculosis and P. jirovecii were 92.1% and 81.4%, respectively, whereas the specificities in detecting M. tuberculosis and P. jirovecii were 98.2% and 100%, respectively.

[Pneumocystis jirovecii and quantitative PCR: Pneumonia or colonization?] / Pneumocytis jirovecii et PCR quantitative : pneumonie ou colonisation à Pneumocystis jirovecii ?

BACKGROUND: Quantitative PCR to detect Pneumocystis jirovecii (Pj) is a new tool for the diagnosis of Pneumocystis jirovecii pneumonia (PJP). The yield of this technique, in cases of low fungal burden, when the standard technique using immunofluorescence (IF) is negative, needs to be evaluated. METHODS: We retrospectively reviewed the charts of all patients with a positive PCR but negative IF test (PCR+/IF-) in bronchoalveolar lavage (BAL) fluid performed over one year. We used an algorithm based on underlying immunosuppression, clinical picture, thoracic CT scan appearances, existence of an alternative diagnosis and the patient's outcome on treatment. Using this, each case was classified as probable PJP, possible PJP or colonization. RESULTS: Among the 416 BAL performed, 48 (12%) were PCR+/IF- and 43 patients were analyzed. Patients were mostly male (56%) with a median age of 60 years. Thirty-five (84%) were immunocompromised: 4 (9%) HIV-infected patients, 26 (60%) with hematologic or solid organ cancer, 3 (7%) were renal transplant recipients. Seven (16%) were classified as probable PPJ and 9 (21%) as possible PJP. Patients with a probable or possible PJP were more frequently admitted to the ICU (P<0.02) and had higher risk of death (P<0.01) when compared to those with colonization. Median PCR levels were very low and were not different between PJP or colonized patients (P=0.23). CONCLUSIONS: Among patients with a positive Pj PCR in BAL but with negative IF, only 37% had probable or possible PJP and PCR could not discriminate PJP from colonization.

[Presence of Pneumocystis carinii and Pneumocystis wakefieldiae DNA in the extrapulmonary tissues of immunocompromised laboratory rats]. / Wystepowanie DNA Pneumocystis carinii i Pneumocystis wakefieldiae w tkankach pozaplucnych szczurów laboratoryjnych poddawanych immunosupresji.

Fungi of the genus Pneumocystis are opportunistic pathogens which cause lethal pneumonia in immunocompromised hosts. Those fungi may also invade other visceral organs where they induce lesions, although, the pathways or mechanisms of the in vivo infection are still unknown. The corticosteroid-treated rat model was used to evaluate the course of extrapulmonary pneumocystosis. Liver, kidney, spleen, and mesenteric lymph nodes of 16 rats were examined for the presence of mtLSU gene fragments of P. carinii and P. wakefieldiae using the nested PCR method. Pneumocystis DNA was detected in 26 organ samples of which 17 contained both species (P. carinii and P. wakefieldiae) and 9 contained only P. carinii. Positive samples were received from 10 rats examined after 6-9 weeks of immunosuppression. The highest percentage of positive samples (62.5%) was obtained among examined visceral lymph nodes. Pneumocystis DNA was detected in the blood serum of two rats with no traces of the DNA in their internal organs. Conversely, Pneumocystis DNA was found in the internal organs of two other rats, although their serum samples were negative. The average number of Pneumocystis cysts in the lungs of animals in which extrapulmonary infection was detected was 3.4 per one microscopic view field. In the case of animals where the infection was limited to the lung tissue this number was almost two times lower (1.8 cysts per one microscopic view field). An analysis of the results of the presently reported experiment showed that massive Pneumocystis infection in the lungs makes it more likely that Pneumocystis will spread to other internal organs. This spread probably takes place via the lymphatic vessels. The extrapulmonary foci may contain either P. carinii alone, or both pathogens: P. carinii and P. wakefieldiae.

Comparative Evaluation Between the RealStar Pneumocystis jirovecii PCR Kit and the AmpliSens Pneumocystis jirovecii (carinii)-FRT PCR Kit for Detecting P. jirovecii in Non-HIV Immunocompromised Patients.

BACKGROUND: Real-time PCR is more sensitive than microscopic examination for detecting Pneumocystis jirovecii. We compared the performance of two assays for detecting P. jirovecii DNA: the RealStar Pneumocystis jirovecii PCR Kit 1.0 CE (Altona Diagnostics, Hamburg, Germany) and the AmpliSens Pneumocystis jirovecii (carinii)-FRT PCR kit (InterLabService Ltd., Moscow, Russia). METHODS: We used 159 samples from the lower respiratory tract (112 bronchoalveolar lavage [BAL] fluid, 37 sputum, and 10 endotracheal aspirate [ETA] samples) of non-HIV immunocompromised patients. Nested PCR and sequencing were used to resolve discordant results. The performance of the two assays was evaluated according to clinical categories (clinical Pneumocystis pneumonia [PCP], possible PCP, or unlikely PCP) based on clinical and radiological observations. RESULTS: The positive and negative percent agreement values were 100% (95% confidence interval [CI], 85.4-100%) and 96.6% (95% CI, 90.9-98.9%), respectively, and kappa was 0.92 (95% CI, 0.84-0.99). P. jirovecii DNA load was significantly higher in the clinical PCP group than in the other groups (P<0.05). When stratified by sample type, the positive rate for BAL fluids from the clinical PCP group was 100% using either assay, whereas the positive rate for sputum/ETA samples was only 20%. CONCLUSIONS: The two assays showed similar diagnostic performance and detected low P. jirovecii burden in BAL fluids. Both assays may be useful as routine methods for detecting P. jirovecii DNA in a clinical laboratory setting, though their results should be interpreted considering sample type.

Inhibition of polymerase chain reaction: Pathogen-specific controls are better than human gene amplification.

PCR inhibition is frequent in medical microbiology routine practice and may lead to false-negative results; however there is no consensus on how to detect it. Pathogen-specific and human gene amplifications are widely used to detect PCR inhibition. We aimed at comparing the value of PCR inhibitor detection using these two methods. We analysed Cp shifts (ΔCp) obtained from qPCRs targeting either the albumin gene or the pathogen-specific sequence used in two laboratory-developed microbiological qPCR assays. 3152 samples including various matrixes were included. Pathogen-specific amplification and albumin qPCR identified 62/3152 samples (2.0%), and 409/3152 (13.0%) samples, respectively, as inhibited. Only 16 samples were detected using both methods. In addition, the use of the Youden's index failed to determine adequate Cp thresholds for albumin qPCR, even when we distinguished among the different sample matrixes. qPCR targeting the albumin gene therefore appears not adequate to identify the presence of PCR inhibitors in microbiological PCR assays. Our data may be extrapolated to other heterologous targets and should discourage their use to assess the presence of PCR inhibition in microbiological PCR assays.

Pneumocystis jirovecii infection of bilateral adrenal glands in an immunocompetent adult: a case report.

Pneumocystis jirovecii (PJ) infection is one of the most common opportunistic infections occurring in patients with HIV/AIDS and other immunocompromised states. It is not known to cause clinically significant illness in immunocompetent hosts. We report a 48-year-old HIV-negative, diabetic male who presented with fever and adrenal insufficiency. Abdominal sonography and PET-CT revealed bilateral enlarged adrenal glands with peripheral enhancement and central necrosis. An endoscopic ultrasound-guided fine-needle aspiration cytology of the left adrenal gland demonstrated well-defined, round cysts of PJ. There was no evidence of pulmonary involvement. The response to first-line treatment was poor and the patient responded to second-line treatment for Pneumocystis infection.

Pneumocystosis in dogs: meta-analysis of 43 published cases including clinical signs, diagnostic procedures, and treatment.

We evaluated 43 published cases of dogs with confirmed Pneumocystis infection regarding the value of clinical parameters indicating the presence of the disease as well as tools for the detection of the pathogen. The assessed parameters included clinical signs, laboratory findings, results of thoracic radiography, autopsy, histopathology, methods for the detection of Pneumocystis, as well as medical therapy. Pneumocystosis was diagnosed most often in certain breeds (Cavalier King Charles Spaniel, Miniature Dachshund) with a predisposition for impaired immunity. The median age of the dogs was 1 y. Chronic therapy-resistant respiratory signs, such as tachypnea, dyspnea, and cough, along with leukocytosis, neutrophilia, and hypogammaglobulinemia, were the most frequently described clinical and clinicopathologic abnormalities. Pneumocystosis can be masked by coinfections with other respiratory pathogens, and the successful detection of Pneumocystis organisms is of major relevance. Several detection methods have been used in the past, but only a few provide reliable results. In 2017, the cytologic evaluation of Giemsa-stained bronchoalveolar lavage samples is generally used, even if sensitivity is only moderate. More reliable results can be achieved using special stains or sensitive molecular techniques. Fast and reliable detection of Pneumocystis is the essential basis for appropriate treatment and higher survival chances for dogs.