Low Prevalence of Pneumocystis pneumonia (PCP) but High Prevalence of Pneumocystis dihydropteroate synthase (dhps) Gene Mutations in HIV-Infected Persons in Uganda

Pneumocystis jirovecii pneumonia (PCP) is an important opportunistic infection in patients infected with HIV, but its burden is incompletely characterized in those areas of sub-Saharan Africa where HIV is prevalent. We explored the prevalence of both PCP in HIV-infected adults admitted with pneumonia to a tertiary-care hospital in Uganda and of putative P. jirovecii drug resistance by mutations in fungal dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr). In 129 consecutive patients with sputum smears negative for mycobacteria, 5 (3.9%) were diagnosed with PCP by microscopic examination of Giemsa-stained bronchoalveolar lavage fluid. Concordance was 100% between Giemsa stain and PCR (dhps and dhfr). PCP was more prevalent in patients newly-diagnosed with HIV (11.4%) than in patients with known HIV (1.1%; p = 0.007). Mortality at 2 months after discharge was 29% overall: 28% among PCP-negative patients, and 60% (3 of 5) among PCP-positive patients. In these 5 fungal isolates and an additional 8 from consecutive cases of PCP, all strains harbored mutant dhps haplotypes; all 13 isolates harbored the P57S mutation in dhps, and 3 (23%) also harbored the T55A mutation. No non-synonymous dhfr mutations were detected. PCP is an important cause of pneumonia in patients newly-diagnosed with HIV in Uganda, is associated with high mortality, and putative molecular evidence of drug resistance is prevalent. Given the reliability of field diagnosis in our cohort, future studies in sub-Saharan Africa can investigate the clinical impact of these genotypes.     

Pneumocystis Jirovecii detection and comparison of multiple diagnostic methods with quantitative real-time PCR in patients with respiratory symptoms

Pneumocystis jirovecii (PCP) remains a significant cause of mortality and morbidity in patients with respiratory infections. Accurate diagnosis of PCP is still a diagnostic challenge. Hence, the main objectives were to study the incidence of Pneumocystis Jirovecii pneumonia infection among respiratory problems patients and to compare the real-time quantitative PCR technique with various diagnostic methodologies. Patients who have respiratory symptoms of PCP like breathlessness, cough, and fever were enrolled. Bronchoalveolar lavage (BAL) samples were collected and homogenized, and then smears were prepared for examination by Gomorimethanamine silver staining (GMSS), Immunofluorescent staining (IFAT), Toludine blue O (TBO), and Giemsa staining. Further, RT-PCR was also performed for the detection of PCP. The mean patients’ age was 52 (SD ± 16) years. 41% were female, and 59% of the patients were male. Weight loss (80%), fever (92%), cough (100%), and dyspnea (76%) were the most common complaints. Twenty-eight patients have been diagnosed with pulmonary infiltrates using chest X-ray. Out of 100 patients, 35% were positive for PCP. The organism was detected using IFAT in all the 35 specimens, 15 of 35 (42.86%) by GMSS, 8 of 35 (17.6%) by Giemsa stain, and 1 of 35 (2.8%) was detected by TBO stains. RT-PCR showed that 39 patients was found to be positive for PCP. Thirty-five of these 39 patients had a positive IFAT (89.74%); the IFAT was negative or undefined in 4 samples. All 39 patients (100%) had signs and symptoms for PCP. Our results suggest that RT-PCR is still the most highly sensitive method for Pneumocystis Jirovecii detection. In poor resource settings where RT-PCR and IFAT is not available, diagnosis of Pneumocystis jirovecii pneumonia remains a complicated issue. In settings where RT-PCR & IFAT are not available, GMSS staining may be the next best choice to detect PCP.     

Genetic Polymorphisms of Pneumocystis Jirovecii in HIV-Positive and HIV-Negative Patients in Northern China

Pneumocystis jirovecii is an opportunistic fungus that can cause severe and potentially fatal Pneumocystis pneumonia (PCP) in immunodeficient patients. In this study, we investigated the genetic polymorphisms of P. jirovecii at eight different loci, including six nuclear genes (ITS, 26S rRNA, sod, dhps, dhfr and β-Tub) and two mitochondrial genes (mtLSU-rRNA and cyb) in three PCP cases, including two patients with HIV infection and one without HIV infection in Shanxi Province, P.R. China. The gene targets were amplified by PCR followed by sequencing of plasmid clones. The HIV-negative patient showed a coinfection with two genotypes of P. jirovecii at six of the eight loci sequenced. Of the two HIV-positive patients, one showed a coinfection with two genotypes of P. jirovecii at the same two of the six loci as in the HIV-negative patient, while the other showed a single infection at all eight loci sequenced. None of the three drug target genes (dhfr, dhps and cyb) showed mutations known to be potentially associated with drug resistance. This is the first report of genetic polymorphisms of P. jirovecii in PCP patients in Shanxi Province, China. Our findings expand our understanding of the genetic diversity of P. jirovecii in China. Open in a separate window     

Clinical Course,Radiological Manifestations,and Outcome of Pneumocystis jirovecii Pneumonia in HIV Patients and Renal Transplant Recipients

BackgroundPneumocystis jirovecii pneumonia (PCP) is a frequent opportunistic infection in immunocompromised patients. In literature, presentation and outcome of PCP differs between patients with human immunodeficiency virus (HIV) infection and renal transplant recipients (RTRs).MethodsWe conducted a cross-sectional study of patients with PCP based on the HIV and renal transplant registries at our institution. Radiological and clinical data from all confirmed PCP cases between 2005 and 2012 were compared.ResultsForty patients were included: 16 with HIV and 24 RTRs. Radiologically, HIV patients had significantly more areas of diffuse lung affection (81% HIV vs. 25% RTR; p = 0.02), more ground glass nodules 5–10 mm (69% vs. 4%; p = <0.001) and enlarged hilar lymph nodes were found only in HIV patients (44%). Cough and dyspnea were the most common clinical signs (>80%) in both groups. Duration from illness onset to hospital presentation was longer in the HIV patients (median of 18 vs. 10 days (p = 0.02)), implying a less fulminant clinical course. Sixty percent of PCP cases in RTRs occurred >12 months after transplantation. Lengths of hospitalization, admission rates to the intensive care unit, and requirements for mechanical ventilation were similar. Outcome in both groups was favourable.ConclusionsWhile important differences in radiological presentation of PCP between HIV patients and RTRs were found, clinical presentation was similar. PCP only rarely presented with fulminant respiratory symptoms requiring ICU admission, with similar results and outcomes for HIV patients and RTRs. Early diagnosis and treatment is mandatory for clinical success.     

Therapeutic Potential of Caspofungin Combined with Trimethoprim-Sulfamethoxazole for Pneumocystis Pneumonia: A Pilot Study in Mice

Pneumocystis pneumonia (PcP) is a major cause of mortality and morbidity in immunocompromised patients. There are limited alternative therapeutic choices to trimethoprim-sulfamethoxazole (TMP-SMX) which is the standard first line therapy/prophylaxis for PcP. The efficacy of low doses of caspofungin and caspofungin in association with TMP-SMX standard-prophylactic dose was evaluated in an experimental model of Pneumocystis. Susceptibility of Pneumocystis spp. to low doses of caspofungin and caspofungin/TMP-SMX was evaluated in Balb/c immunosuppressed mice, infected intranasally with P. murina. Caspofungin was administered once daily at 0.1 mg/kg, 0.05 mg/kg, and 0.001 mg/kg and TMP-SMX was administered by oral gavage (12.25 mg/62.5 mg/day), for 21 days. Efficacy was calculated based on the reduction in organism burden determined through quantitative fluorescent-based real-time PCR (qPCR). Serum β-1,3-D-glucan was measured as an additional marker of infection. The present data showed that caspofungin demonstrated anti-Pneumomocystis effect. However, the doses administrated were too low to achieve Pneumocystis eradication, which suggests that echinocandin treatment should not be administrated as mono-therapy. After 21 days of treatment, P. murina was not detected in the lungs of mice with either TMP-SMX or caspofungin/TMP-SMX. The results showed that, even at the lowest concentrations tested, the efficacy of caspofungin in association with TMP-SMX was higher than the efficacy of either drug used alone. The administration of caspofungin/TMP-SMX was at least 1.4 times more effective against P. murina infection than TMP-SMX used alone. The most promising result was achieved with the combination of caspofungin 0.05 mg/kg/day with TMP-SMX 12.5 mg–62.5 mg/day, which reduced the parasite burden to undetectable levels immediately at the 14^th day of treatment, showing a highly marked anti-Pneumomocystis effect. These data suggest that the administration of low doses of caspofungin in combination with low doses of TMP-SMX may provide an improved treatment protocol for Pneumocystis infection clearance.     

卡泊芬净联合复方磺胺甲噁唑治疗艾滋病合并肺孢子菌肺炎

目的探讨卡泊芬净联合复方磺胺甲噁唑(TMP-SMX)治疗艾滋病合并肺孢子菌肺炎(PCP)的疗效。方法回顾性总结分析9例艾滋病合并肺孢子菌肺炎的临床资料,包括临床特点及诊疗经过。结果 9例患者临床诊断PCP成立,经卡泊芬净联合TMP-SMX抗PCP治疗后,除1例死亡(老年患者合并慢性支气管炎病史)外,其余8例均得到满意疗效。结论卡泊芬净联合TMP-SMX治疗艾滋病合并PCP,可达到良好的治疗效果。     

Pneumocystis jirovecii Pneumonia in Tropical and Low and Middle Income Countries: A Systematic Review and Meta-Regression

Objective

Pneumocystis jirovecii pneumonia (PCP), the commonest opportunistic infection in HIV-infected patients in the developed world, is less commonly described in tropical and low and middle income countries (LMIC). We sought to investigate predictors of PCP in these settings.

Design

Systematic review and meta-regression.

Methods

Meta-regression of predictors of PCP diagnosis (33 studies). Qualitative and quantitative assessment of recorded CD4 counts, receipt of prophylaxis and antiretrovirals, sensitivity and specificity of clinical signs and symptoms for PCP, co-infection with other pathogens, and case fatality (117 studies).

Results

The most significant predictor of PCP was per capita Gross Domestic Product, which showed strong linear association with odds of PCP diagnosis (p<0.0001). This was not explained by study design or diagnostic quality. Geographical area, population age, study setting and year of study also contributed to risk of PCP. Co-infection was common (444 episodes/1425 PCP cases), frequently with virulent organisms. The predictive value of symptoms, signs or simple tests in LMIC settings for diagnosis of PCP was poor. Case fatality was >30%; treatment was largely appropriate. Prophylaxis appeared to reduce the risk for development of PCP, however 24% of children with PCP were receiving prophylaxis. CD4 counts at presentation with PCP were usually <200×10^3/ml.

Conclusions

There is a positive relationship between GDP and risk of PCP diagnosis. Although failure to diagnose infection in poorer countries may contribute to this, we also hypothesise that poverty exposes at-risk patients to a wide range of infections and that the relatively non-pathogenic P. jirovecii is therefore under-represented. As LMIC develop economically they eliminate the conditions underlying transmission of virulent infection: P. jirovecii, ubiquitous in all settings, then becomes a greater relative threat.     

A pulmonary paragonimiasis case mimicking metastatic pulmonary tumor

Pulmonary paragonimiasis is a relatively rare cause of lung disease revealing a wide variety of radiologic findings, such as air-space consolidation, nodules, and cysts. We describe here a case of pulmonary paragonimiasis in a 27-year-old woman who presented with a 2-month history of cough and sputum. Based on chest computed tomography (CT) scans and fluorodeoxyglucose positron emission tomography (FDG-PET) findings, the patient was suspected to have a metastatic lung tumor. However, she was diagnosed as having Paragonimus westermani infection by an immunoserological examination using ELISA. Follow-up chest X-ray and CT scans after chemotherapy with praziquantel showed an obvious improvement. There have been several reported cases of pulmonary paragonimiasis mimicking lung tumors on FDG-PET. However, all of them were suspected as primary lung tumors. To our knowledge, this patient represents the first case of paragonimiasis mimicking metastatic lung disease on FDG-PET CT imaging.     

Lymphoid interstitial pneumonia.

A 19-year-old man presented with dyspnea, cough and chest pains; he also complained of nausea, anorexia and postprandial vomiting and reported a 10-kg weight loss. Generalized lymphadenopathy and some rales over both lung bases were noted and a chest radiograph showed bilateral nodular lesions. Persistent leukocytosis, thrombocytosis, proteinuria and anergy to a series of natural antigens were found. The diagnosis of lymphoid interstitial pneumonia was made from material obtained at open lung biopsy. Rapid but incomplete clearing of the lung lesions resulted from steroid therapy; the other abnormalities were corrected gradually, except for the proteinuria, which persisted. The clinical improvement and the ability to work and play have been maintained for the past 20 months.     

Pneumocystis Pneumonia in HIV-Infected and Immunocompromised Non-HIV Infected Patients: A Retrospective Study of Two Centers in China

Background

Pneumocystis pneumonia (PCP) is an emerging infectious disease in immunocompromised hosts. However, the clinical characteristics of these patients are poorly understood in mainland China.

Methods

We performed a retrospective study of PCP from 2008 to 2012. Information was collected regarding clinical manifestations, hospitalization, and outcome. A prognostic analysis was performed using a Cox regression model.

Results

151 cases of PCP were included; 46 non-HIV and 105 HIV cases. All-cause mortality (15.2% vs. 12.4%, p = 0.64) and the results of time-to-event analysis (log-rank test, p = 0.62) were similar between non-HIV and HIV infected cases, respectively. From 2008 to 2012, time from admission to initial treatment in non-HIV infected PCP patients showed declining trend [median (range) 20 (9–44) vs. 12 (4–24) vs. 9 (2–23) vs. 7 (2–22) vs. 7 (1–14) days]. A similar trend was observed for all-cause mortality (33.3% vs. 20.0% vs.14.3% vs. 14.3% vs. 6.7%). Patients with four or more of the following clinical manifestations (cough, dyspnea, fever, chest pain, and weight loss) [adjusted HR (AHR) 29.06, 95% CI 2.13–396.36, P = 0.01] and admission to intensive care unit (ICU) [AHR 22.55, 95% CI 1.36–375.06, P = 0.03] were independently associated with all-cause mortality in non-HIV infected PCP patients. Variables associated with mortality in HIV infected PCP patients were admission to ICU (AHR 72.26, 95% CI 11.76–443.87, P<0.001) and albumin ≤30 g/L (AHR 9.93 95% CI 1.69–58.30, P = 0.01).

Conclusions

Upon admission comprehensive clinical assessment including assessment of four or more clinical manifestations (cough, dyspnea, fever, chest pain, and weight loss) in non-HIV infected PCP patients and albumin ≤30 g/L in HIV infected patients might improve prognosis.     

Cost-effectiveness analysis of diagnostic options for pneumocystis pneumonia (PCP)

Background

Diagnosis of Pneumocystis jirovecii pneumonia (PCP) is challenging, particularly in developing countries. Highly sensitive diagnostic methods are costly, while less expensive methods often lack sensitivity or specificity. Cost-effectiveness comparisons of the various diagnostic options have not been presented.

Methods and Findings

We compared cost-effectiveness, as measured by cost per life-years gained and proportion of patients successfully diagnosed and treated, of 33 PCP diagnostic options, involving combinations of specimen collection methods [oral washes, induced and expectorated sputum, and bronchoalveolar lavage (BAL)] and laboratory diagnostic procedures [various staining procedures or polymerase chain reactions (PCR)], or clinical diagnosis with chest x-ray alone. Our analyses were conducted from the perspective of the government payer among ambulatory, HIV-infected patients with symptoms of pneumonia presenting to HIV clinics and hospitals in South Africa. Costing data were obtained from the National Institutes of Communicable Diseases in South Africa. At 50% disease prevalence, diagnostic procedures involving expectorated sputum with any PCR method, or induced sputum with nested or real-time PCR, were all highly cost-effective, successfully treating 77–90% of patients at $26–51 per life-year gained. Procedures using BAL specimens were significantly more expensive without added benefit, successfully treating 68–90% of patients at costs of $189–232 per life-year gained. A relatively cost-effective diagnostic procedure that did not require PCR was Toluidine Blue O staining of induced sputum ($25 per life-year gained, successfully treating 68% of patients). Diagnosis using chest x-rays alone resulted in successful treatment of 77% of patients, though cost-effectiveness was reduced ($109 per life-year gained) compared with several molecular diagnostic options.

Conclusions

For diagnosis of PCP, use of PCR technologies, when combined with less-invasive patient specimens such as expectorated or induced sputum, represent more cost-effective options than any diagnostic procedure using BAL, or chest x-ray alone.     

<Emphasis Type="BoldItalic">Pneumocystis Jirovecii</Emphasis> Pneumonia: Current Knowledge and Outstanding Public Health Issues

Antiretroviral therapy and cotrimoxazole prophylaxis have caused a decline in Pneumocystis jirovecii incidence in developing countries since the 1990s. Nevertheless, Pneumocystis jirovecii pneumonia (PCP) remains the primary AIDS-defining disease around the world. Much about the disease remains unknown, including its global burden, best diagnostic practices, the frequency of drug resistance, and the risks associated with Pneumocystis colonization. This review describes current knowledge about Pneumocystis infection and highlights areas where new research could benefit public health.     

Pulmonary Schizophyllum commune infection developing mucoid impaction of the bronchi

A 54-year-old woman was admitted for cough, sputum, and an abnormal chest X-ray shadow. Bronchoscopy showed mucoid impaction of the bronchi (MIB). Histopathologic evidence of mucous plugs was consistent with one component of allergic bronchopulmonary mycosis. Schizophyllum commune (S. commune) was identified. Two attempts at removal of the mucous plugs were unsuccessful. Itraconazole was then administered, and the mucous plugs disappeared. There are few reports of MIB due to S. commune; we herein report a case of MIB due to S. commune infection.     

Roentgenological picture of pneumonia caused by Legionella: on the materials of outbreak in town Verkhnyaya Pyshma

Chest X-ray is the most common and widely used diagnostic procedure. Chest X-ray is frequently performed not only due to lungs diseases but also in other organs' diseases which indirectly affects lungs. At present computer tomography (CT) which has high resolution becomes to be more and more important. As in other diagnostic method, the main aim of CT is to confirm or reject the presence of disease. During outbreak of pneumonia in town Verkhnyaya Pyshma (Sverdlovsk region), all patients with suspected legionellosis underwent chest X-ray in front and lateral views. In several cases, computer tomography was performed.     

机化性肺炎患者的CT引导下经皮肺穿刺活检及其临床诊治分析

目的:探讨CT引导下经皮肺穿刺活检对机化性肺炎患者的诊断价值,并总结机化性肺炎的临床诊治经验。方法:回顾性分析2015年7月-2017年9月在南京医科大学附属常州第二人民医院住院行CT引导下经皮肺穿刺活检取得肺部病灶组织确诊为机化性肺炎的14例患者,所有患者行CT引导下经皮肺穿刺活检,总结机化性肺炎患者的临床诊治经验。结果:14例机化性肺炎患者平均年龄为59岁,平均起病时间为21天。主要临床症状以发热、咳嗽、咳痰为主。6例肺部听诊可闻及湿啰音。影像学检查主要表现为肺部斑片状不均匀密度增高影。所有患者初次就诊时均未首先诊断考虑机化性肺炎。所有患者入院后均行CT引导下经皮肺穿刺活检术,术后病理均确诊为机化性肺炎,术中3例出现少量气胸,4例出现少量出血,予吸氧止血等对症处理后好转。14例患者予糖皮质激素治疗后,主要临床症状改善,影像学检查均较前吸收好转。结论:对于持续性干咳、呼吸困难、发热病人,抗生素疗效差,影像学显示片状或块状影病灶,特别是游走性斑片阴影,需要高度警惕机化性肺炎。CT引导下经皮肺穿刺活检可作为明确机化性肺炎诊断的首选方法。机化性肺炎对糖皮质激素治疗敏感,可出现可逆性的好转,一旦确诊,建议及早使用糖皮质激素治疗。     

99mTc-human immunoglobulin (HIG) in AIDS patients: first results

Scintigraphy with 99mTc labelled human polyclonal immunoglobulin was performed in 16 patients with ascertained or suspected AIDS-related infections. 99mTc-HIG lung scanning was compared, in 11 patients, with 67Ga scintigraphy, chest X-ray and high resolution lung CT. 67Ga and 99mTc-HIG were concordantly positive in five cases of BAL-ascertained Pneumocystis carinii pneumonia (PCP), while one of them was Rx and CT negative. X-ray, 67Ga and 99mTc were concordantly negative in 5 cases. 99mTc-HIG yielded negative results in two cases of Mycobacterium infection, both of which were 67Ga and Rx positive: Mycobacterium avium in diffuse lung involvement and Mycobacterium TBC in excavated infiltrate. 99mTc-HIG was also positive in other 3 AIDS patients: 1 case of intestinal cryptosporidiosis, 1 pulmonary abscess (Staphylococcus and Candida), and 1 sacral abscess; it was negative in 1 case of Kaposi sarcoma (also 201Tl negative). In conclusion, 99mTc-HIG scintigraphy in AIDS patients is feasible, and offers some practical advantages (continuous availability, fast response time, etc.). The initial results seem similar to those of 67Ga in lung scanning (and perhaps more specific for PCP).     

Cloning of the Pneumocystis jirovecii trifunctional FAS gene and complementation of its DHPS activity in Escherichia coli

Pneumocystis pneumonia or PCP is caused by Pneumocystis jirovecii, an obligate parasite of the human lung. In this study P. jirovecii genomic sequence encoding FAS, a trifunctional protein including dihydroneopterin aldolase (DHNA), hydroxymethyldihydropterin pyrophosphokinase (PPPK) and dihydropteroate synthase (DHPS) were identified by PCR amplification from fixed broncheolar lavage samples from patients having Pneumocystis pneumonia. The P. jirovecii trifunctional DHNA-PPPK-DHPS genes (PjFAS) showed a high degree of conservation with the rat Pneumocystis carinii and P. carinii f. sp. macaca sequences. To test the functionality of the PjFAS sequences introns were removed followed by cloning and expression of PjFAS sequences in a DHPS-disrupted Escherichia coli strain. Complementation depended on the presence of N-terminal FAS sequences in addition to a glutathione S- transferase tag to the N-terminus of PjFAS. Functional complementation allowed evaluation of DHPS mutations implicated with sulfa drug resistance.     

Potential Impact of Co-Infections and Co-Morbidities Prevalent in Africa on Influenza Severity and Frequency: A Systematic Review

Infectious diseases and underlying medical conditions common to Africa may affect influenza frequency and severity. We conducted a systematic review of published studies on influenza and the following co-infections or co-morbidities that are prevalent in Africa: dengue, malaria, measles, meningococcus, Pneumocystis jirovecii pneumonia (PCP), hemoglobinopathies, and malnutrition. Articles were identified except for influenza and PCP. Very few studies were from Africa. Sickle cell disease, dengue, and measles co-infection were found to increase the severity of influenza disease, though this is based on few studies of dengue and measles and the measles study was of low quality. The frequency of influenza was increased among patients with sickle cell disease. Influenza infection increased the frequency of meningococcal disease. Studies on malaria and malnutrition found mixed results. Age-adjusted morbidity and mortality from influenza may be more common in Africa because infections and diseases common in the region lead to more severe outcomes and increase the influenza burden. However, gaps exist in our knowledge about these interactions.     

Low infectivity of Plasmodium falciparum gametocytes to Anopheles gambiae following treatment with sulfadoxine-pyrimethamine in Mali

Sulfadoxine-pyrimethamine (SP) treatment increases the rate of gametocyte carriage and selects SP resistance-conferring mutations in Plasmodium falciparum dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS), raising concerns of increased malaria transmission and spread of drug resistance. In a setting in Mali where SP was highly efficacious, we measured the prevalence of DHFR and DHPS mutations in P. falciparum infections with microscopy-detected gametocytes following SP treatment, and used direct feeding to assess infectivity to Anopheles gambiae sensu lato. Children and young adults presenting with uncomplicated malaria were treated with SP or chloroquine and followed for 28 days. Gametocyte carriage peaked at 67% 1 week after treatment with a single dose of SP. Those post-SP gametocytes carried significantly more DHFR and DHPS mutations than pre-treatment asexual parasites from the same population. Only 0.5% of 1728 mosquitoes fed on SP-treated gametocyte carriers developed oocysts, while 11% of 198 mosquitoes fed on chloroquine-treated gametocyte carriers were positive for oocysts. This study shows that in an area of high SP efficacy, although SP treatment sharply increased gametocyte carriage, the infectiousness of these gametocytes to the vector may be very low. Accurate and robust methods for measuring infectivity are needed to guide malaria control interventions that affect transmission.