Pneumocystis carinii pneumonia in Hong Kong: a 10 year retrospective study

Epidemiology, mortality and effectiveness of prophylaxis for Pneumocystis jiroveci pneumonia among rheumatic patients: a territory-wide study

Background

Pneumocystis jiroveci pneumonia (PJP) is an opportunistic infection affecting immunocompromised individuals. However, evidence regarding the burden and effectiveness of prophylaxis among rheumatic patients remains limited. Delineating the epidemiology and efficacy of prophylaxis among rheumatic patients is urgently needed.

Methods

We performed a territory-wide cohort study of rheumatic patients in Hong Kong. All patients with a diagnosis of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV), immune-mediated myositis (IMM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or spondyloarthritis (SpA) between 2015 and 2019 were included. Prevalence, frequency of prophylaxis and mortality of PJP were calculated. Number needed to treat (NNT) analysis was also performed.

Results

Out of 21,587 patients (54% RA, 25% SLE, 13% SpA, 5% IMM, 2% AAV and 1% SSc), 1141 (5.3%) patients were prescribed PJP prophylaxis. 48/21,587 (0.2%) developed PJP. No patients who developed PJP received prophylaxis prior to infection. The incidence of PJP was highest among SSc, AAV, and IMM patients. Among these diseases, the majority of PJP occurred while patients were on glucocorticoids at daily prednisolone-equivalent doses of 15 mg/day (P15) or above. PJP prophylaxis was effective with NNT for SSc, AAV and IIM being 36, 48 and 114 respectively. There were 19 PJP-related mortalities and the mortality rate was 39.6%.

Conclusion

PJP is an uncommon but important infection among rheumatic patients, PJP prophylaxis is effective and should be considered in patients with SSc, AAV and IMM, especially those receiving glucocorticoid doses above P15.

Renal Involvement in Congenital Cytomegalovirus Infection: A Systematic Review

Background: Congenital cytomegalovirus (cCMV) infection is the most frequent mother-to-child transmitted infection worldwide and a prevalent cause of neonatal disease and long-term morbidity. The kidney is a target organ for CMV, which replicates in renal tubules and is excreted in large quantities in urine for years in children with cCMV infection. Nonetheless, kidney disease has rarely been reported in cCMV-infected patients. Objective: We aimed to describe the available data on renal involvement in patients with cCMV infection at the pathologic, functional, anatomical, and/or clinical levels. Methods: A systematic search was performed in the MEDLINE/PubMed, SCOPUS, and Cochrane databases. Studies describing any renal involvement in fetuses or neonates aged ≤3 weeks at diagnosis of microbiologically confirmed cCMV infection were eligible. Results: Twenty-four articles were included, with a very low level of evidence. Pathologic findings in autopsy studies universally described CMV typical inclusion bodies in tubular cells. No functional studies were identified. cCMV infection was not associated with an increased risk of kidney malformations. Congenital nephrotic syndrome was the most common clinical condition associated with cCMV, but a causal relationship cannot be established. Conclusions: Typical pathological features of cCMV infection are very common in renal tissue, but they do not seem to entail significant consequences at the anatomical or clinical levels.

Acute interstitial pneumonia in foals: A severe, multifactorial syndrome with lung tissue recovery in surviving foals

BACKGROUND

Acute interstitial pneumonia in foals has been sparsely described in literature, and the individual authors disagree on the underlying aetiology. Histopathological follow-up from surviving foals is not available.

OBJECTIVES

Description of clinical and histopathological findings in the course of acute interstitial pneumonia and in recovery. Investigating the aetiology and possible triggering factors of acute interstitial pneumonia.

STUDY DESIGN

Case series.

METHODS

Post-mortem examination of nine affected foals; seven died during the acute phase, and two had recovered from acute interstitial pneumonia. Data from clinical examinations on the day of death were recorded for all foals. Complete necropsy, special histological staining, virological and microbiological examinations were performed.

RESULTS

Seven foals died during the acute phase with severe respiratory distress, fever and increased numbers of comet tail artefacts in lung ultrasound. In post-mortem examination, a wide variety of possible triggering factors was identified. Microbiology revealed Escherichia coli, Rhodococcus equi and Klebsiella pneumoniae as the most common bacterial pathogens. Equine herpesvirus 2 was detected in all foals by PCR. Those with high viral loads also displayed histopathological changes suggestive of viral infections. Pneumocystis carinii was detected in all acutely affected foals. Histopathological changes in lung parenchyma clearly differed between the foals that had recovered from acute interstitial pneumonia and those dying in the acute phase. While lungs in acute phase featured marked parenchymal collapse and necrosis, the recovered foals revealed nearly normal ventilated lung parenchyma and alveolar structure.

MAIN LIMITATIONS

Small number of cases. Because all foals are from the same breeding farm with endemic occurrence of pathogens, it is not certain whether the results of this study can be transferred to other foals without restrictions.

CONCLUSIONS

Acute interstitial pneumonia seems to be based on a multifactorial aetiology. Lungs from foals that have survived acute interstitial pneumonia appear to be able to regenerate completely, leaving no permanent changes.

Pneumocystis pneumonia in HIV patients: a diagnostic challenge till date

HIV has become a major health problem in India, patients commonly succumb to opportunistic infections (OIs), respiratory infections being an important cause of morbidity and their accurate diagnosis is still a challenge. Our aim was to study the occurrence of Pneumocystis pneumonia (PCP) in HIV/AIDS patients with respiratory complaints attending ART clinic and to compare various diagnostic methodologies. One hundred and twenty five HIV/AIDS patients presenting with respiratory symptoms like cough, fever, breathlessness etc, were enrolled, and induced sputum samples were collected. Samples were homogenized using glass beads and Dithiothretol. Smears were prepared and examined by Immunoflourescent staining (IFAT), Gomori methanamine silver staining (GMSS), Toludine blue O staining (TBO) and Giemsa staining for Pneumocystis jiroveci. Among the 125 patients who presented with respiratory complaints, 34 cases (27.2%) were diagnosed as having PCP. All 34 cases were detected by IFAT followed by GMSS, Giemsa and Toludine blue O staining in decreasing order. The mean CD4 count was 67.27cells/μl. PCP has become an important health problem in HIV/AIDS patients with low CD4 counts in India. IFAT remains the most sensitive method for the detection of this uncultivable organism. In resource poor settings where an immunoflourecent microscope is not available, diagnosis of PCP still remains problematic.

Pneumocystis jirovecii pneumonia in patients with end-stage renal disease: a comparison with the general population

BACKGROUND

Data on occurrence and risk factors for pneumocystis pneumonia (PCP) in patients with end-stage renal disease (ESRD) are sparse.

METHODS

This was a nationwide population-based study assessing occurrence and risk factors for PCP among patients with ESRD and population controls over a 21-year period (1/1 1990 to 31/12 2010). Using Danish registry data, first-time diagnoses of PCP were identified.

RESULTS

We identified 13 296 adult patients with ESRD and 244 255 controls, yielding 63 560 and 2 223 660 person-years of follow-up (PYFU), respectively. Fifty-eight first-time diagnoses of PCP were recorded in the ESRD group. Forty-six episodes occurred among renal transplant recipients (RTx) and 12 among haemodialysis patients (HD), yielding incidence rates of 181 (136-242) and 43.1 (24.5-75.9) per 100 000 PYFU. Compared to population controls, we found incidence rate-ratios of 125.9 (78.4-204) among RTx and 29.9 (14.1-59.7) among HD patients. Risk factors for PCP in RTx were age 50-65 years, age > 65 years, diabetes, polycystic kidney disease and hypertensive kidney disease/nephrosclerosis with an IRR of 2.22 (1.14-4.31), 3.12 (1.35-7.21), 3.44 (1.16-10.2), 4.25 (1.55-11.7) and 3.87 (1.49-10.0), respectively, and more than 36 months of dialysis before transplantation with an IRR of 1.99 (1.03-3.84). Among RTx the risk of PCP was highest during the first 6 months post-transplantation and increased from the beginning (IR1990-94 = 111 (46.3-267) per 100 000 PYFU) towards the end of the study period (IR2005-10 = 299 (203-439)).

CONCLUSION

The PCP risk is substantial in RTx within the first 6 months of transplantation, emphasizing the potential benefit of prophylactic treatment in the early post-transplant period. Importantly, we identified subgroups within the RTx group that require more attention.

Molecular epidemiology of Pneumocystis jiroveci in human immunodeficiency virus-positive and -negative immunocompromised patients in The Netherlands

Pneumocystis jiroveci infections can cause pneumocystis pneumonia (PCP) or lead to colonization without signs of PCP. Over the years, different genotypes of P. jiroveci have been discovered. Genomic typing of P. jiroveci in different subpopulations can contribute to unravelling the pathogenesis, transmission and spread of the different genotypes. In this study, we wanted to determine the distribution of P. jiroveci genotypes in immunocompetent and immunocompromised patients in The Netherlands and determine the clinical relevance of these detected mutations. A real-time PCR targeting the major surface glycoprotein gene (MSG) was used as a screening test for the presence of P. jiroveci DNA. Samples positive for MSG were genotyped based on the internal transcribed spacer (ITS) and dihydropteroate synthase (DHPS) genes. Of the 595 included bronchoalveolar lavage fluid samples, 116 revealed the presence of P. jiroveci DNA. A total of 52 of the 116 samples were ITS genotyped and 58 DHPS genotyped. The ITS genotyping revealed 17 ITS types, including two types that have not been described previously. There was no correlation between ITS genotype and underlying disease. All ITS- and DHPS-genotyped samples were found in immunocompromised patients. Of the 58 DHPS-genotyped samples, 50 were found to be WT. The other eight samples revealed a mixed genotype consisting of WT and type 1. The majority of the latter recovered on trimethoprim-sulfamethoxazole suggesting no clinical relevance for this mutation.

Clinical conditions associated with PCP in children

Pneumocystis jirovecii is a leading cause of opportunistic infections among the immune compromised. During the 1980s, attention focused on patients with HIV, however, with the advent of anti-retroviral therapy, we wished to revisit the question of underlying diseases associated with Pneumocystis pneumonia in children. We identified 80 cases from 1986 to 2006 and performed a retrospective chart review to identify clinical characteristics for each of the cases. HIV was the single most common associated underlying condition seen in this cohort, accounting for 39% of the cases overall, however, it was seen in just 15% of the cases since 1998. Transplant recipients and oncology patients together comprised another 39% of the cases, with 9% of cases attributed to primary immune deficiency and another 9% of cases associated with less well-recognized causes of susceptibility. This study documents the ongoing need for vigilance to diagnose Pneumocystis pneumonia in less well-recognized clinical scenarios.

Pneumocystis jirovecii Pneumonia

Pneumocystis jirovecii has gained attention during the last decade in the context of the AIDS epidemic and the increasing use of cytotoxic and immunosuppressive therapies. This article summarizes current knowledge on biology, pathophysiology, epidemiology, diagnosis, prevention, and treatment of pulmonary P jirovecii infection, with a particular focus on the evolving pathophysiology and epidemiology. Pneumocystis pneumonia still remains a severe opportunistic infection, associated with a high mortality rate.

Analysis of USRDS: incidence and risk factors for Pneumocystis jiroveci pneumonia

BACKGROUND

To investigate the effect of modern immunosuppression on the incidence, risk factors, morbidity, and mortality of Pneumocystis pneumonia (PCP) in recipients of kidney transplants.

METHODS

We conducted a retrospective cohort study of 32,757 Medicare primary transplant recipients in the United States Renal Data System from January 1, 2000 through July 31, 2004. PCP infection was defined by Medicare claims using International Classification of Disease, 9th Revision codes. The incidence of PCP infections, graft loss, and death were measured.

RESULTS

There were a total of 142 cases (cumulative incidence 0.4%) of PCP after kidney transplantation during the study period. By using multivariate analysis with Cox regression, expanded criteria donor, donation after cardiac death, and earlier year of transplant were associated with development of PCP disease. Induction immunosuppression and acute rejections were not associated with risk for PCP infections. However, based on adjusted hazard ratio (AHR), maintenance immunosuppression regimens containing the combination of tacrolimus and sirolimus (AHR 3.60, confidence interval [CI] 2.03-6.39), Neoral and mycophenolate mofetil (AHR 2.09, CI 1.31-3.31), and sirolimus and mycophenolate mofetil (AHR 2.77, CI 1.40-5.47), were associated with development of PCP. As a time dependent variable, PCP was associated with an increased risk of both graft loss and death.

CONCLUSION

PCP infections are rare in the modern era of prophylaxis; however, these infections are a serious risk factor for graft loss and patient death, in particular, in patients who are on sirolimus as part of the immunosuppressive regimen. The median time to development of PCP after transplant was 0.80+/-0.95 years, suggesting a longer period of PCP prophylaxis.

Risk and predictors of infection leading to hospitalisation in a large primary-care-derived cohort of patients with inflammatory polyarthritis

BACKGROUND

The increased mortality observed in patients with rheumatoid arthritis is partly due to an increased occurrence of serious infections. A retrospective study from the Mayo Clinic found that infection risk is increased in rheumatoid arthritis. In particular, serious infection was associated with severe disease and use of corticosteroids. Robust estimates are required from prospective studies of incident cases.

OBJECTIVE

To examine the risk of infection leading to hospitalisation and potential factors associated with this risk in an unselected population of patients with inflammatory polyarthritis.

DESIGN

A prospective cohort study comparing infection incidence in new-onset patients with inflammatory polyarthritis with local population experience.

PATIENTS AND METHODS

2108 patients with inflammatory polyarthritis from a community-based register were studied and followed up annually (median 9.2 years). The rate of hospitalisations for serious infection was compared with the rate of hospitalisations in the regional population. The contribution of potential predictors was assessed by undertaking a within-cohort analysis.

RESULTS

Overall, the incidence of infection was more than two and a half times that of the general population (varying by site). History of smoking, corticosteroid use and rheumatoid factor were found to be significantly independent predictors of infection-related hospitalisation. Patients with inflammatory polyarthritis with all three factors were more than seven times as likely to be hospitalised compared with the rest of the cohort.

DISCUSSION

These findings provide background data on the risk of infection associated with rheumatoid arthritis, and are of particular interest given the current awareness of the risk of infection associated with anti-tumour necrosis factoralpha treatments.