HIV-negative Immunocompromised Patients Research Articles

Outcome of Pneumocystis pneumonia in transplant and non-transplant HIV-negative immunocompromised patients.

Previous studies showed HIV-negative immunocompromised patients are susceptible to Pneumocystis pneumonia (PCP). However, the PCP outcome has not been compared among HIV-negative immunocompromised patients. In this retrospective cohort study at the University Health Network, we included all HIV-negative immunocompromised patients who fulfilled the European Organization for Research and Treatment of Cancer (EORTC) PCP diagnosis criteria from December 2018 to December 2019. We compared the demographics, comorbidities, course of illness, and PCP outcome (28-day mortality and composite outcome [i.e., death or intensive care unit (ICU) admission]) between solid organ transplant (SOT) and non-SOT patients. Of 160 non-HIV patients with PCP diagnoses, 118 patients fulfilled EORTC criteria (76 males [64.4%], median [range] age: 65.5 [21-87] years). PCP presentation in SOT recipients (n=14) was more severe than non-SOT patients (n=104): acute presentation (onset <7 days before admission: 11/14 [78.6%] vs. 51/104 [56%], p=.037), shortness of breath (100% vs. 75/104 [74.3%], p=.037), median [range] O2 saturation (88% [75%, 99%] vs. 92%[70%, 99%], p=.040), and supplemental O2 requirement (12/14 [85.7%] vs. 59/104 [56.7%], p=.044). The mortality [4/14, (28.6%) vs. 15/104 (14.4%), p=.176], ICU admission (10/14 [71.4%] vs. 18/104 [17.3%], p<.0001), and mechanical ventilation (8/14 [57.1%] vs. 18/104 [17.3%], p=.0007) in SOT patients was different from non-SOT patients. In multivariable analysis, SOT recipients were at greater risk of composite outcome than non-SOT patients (aOR [CI95%]: 12.25 [3.08-48.62], p<.001). PCP presentation and outcomes in SOT recipients are more severe than in non-SOT patients. Further studies are required to explore the biological reasons for this difference.

Supplementary Role of Immunological Indicators in the Diagnosis and Prognosis of Pneumocystis Pneumonia in Non-HIV Immunocompromised Patients.

BackgroundPneumocystis pneumonia (PCP) has a high mortality in HIV-negative immunocompromised patients. The occurrence and development of PCP are believed to be correlated with the level of lymphocytes and their subsets. The aim of this study was to determine if the levels of lymphocyte subpopulations and immunoglobulin are associated with PCP.MethodsA total of 74 immunocompromised patients were enrolled in this single-center cohort study. Diagnosis of PCP was based on the relevant pulmonary symptoms and radiological imaging, and the detection of Pneumocystis jirovecii in BAL fluid or biopsy tissue by metagenomic next-generation sequencing (mNGS). All patients were divided into two groups (PCP group and non-PCP group) and the patients in PCP group were then divided into two groupsbased on the outcome of the disease during the hospitalization.ResultsWe observed a significant lower level of IgG (p=0.000) and B lymphocyte counts (p=0.017) in the PCP group comparing to that in the non-PCP group. CD4+ T cell counts, as well as the ratio of CD4+/CD8+ T cells in circulation and BAL fluid were also lower in the PCP group comparing to those in the non-PCP group. Lactate dehydrogenase (LDH) in the PCP group was significantly higher than that in the non-PCP group (p=0.029). In the PCP group, a lower level of total lymphocytes (p=0.004), T cells (p=0.001), CD4+ cells (p=0.001), and CD8+ cells (p=0.007), as well as the proportion of lymphocytes in BAL fluid (p=0.000) were found in deceased patients comparing to those in the survived group.ConclusionOur study revealed an important role of humoral immunity in the infection of Pneumocystis jirovecii. The level of B cells and IgG could be used as a supplement to predict the occurrence of PCP. The level of CD4+ and CD8+ lymphocytes was significantly correlated with the outcome of PCP.

A Negative (1,3)-β-D-Glucan Result Alone Is Not Sufficient to Rule Out a Diagnosis of Pneumocystis Pneumonia in Patients With Hematological Malignancies.

Background: Serum (1,3)-β-D-glucan (BG) testing is increasingly being used in the diagnostic armamentarium for invasive fungal diseases. Given its high sensitivity, some studies suggest that a negative BG result contributes to rule out a diagnosis of Pneumocystis pneumonia (PCP). However, recent reports described a suboptimal sensitivity in HIV-negative immunocompromised patients. In this study, we evaluated the performance of BG assay for PCP diagnosis in HIV-negative patients with diverse PCP risk factors. We also assessed the correlation between Pneumocystis jirovecii load in pulmonary samples and serum BG levels.Methods: We retrospectively included HIV-negative patients with microscopically proven PCP and for whom a BG result was available. We also enrolled patients colonized by Pneumocystis as control group. Colonized patients were matched with PCP patients based on their underlying condition that exposed to PCP. Pulmonary fungal loads were determined by an in-house real-time PCR, and BG levels were measured by using the Fungitell® kit (Associates of Cape Cod, Inc.).Results: Thirty-nine patients were included in each of the two groups. Thirty-four of 39 PCP patients and one of 39 colonized patient had a positive BG test, resulting in a sensitivity of 0.87 (95% CI: 0.73–0.94), a specificity of 0.97 (95% CI: 0.87–0.99), a positive predictive value of 0.97 (95% CI: 0.85–0.99), and a negative predictive value of 0.88 (95% CI: 0.75–0.95) for BG assay. Nonetheless, median BG level differed according to the underlying condition. Among the PCP group, the lowest median level of 211 pg/ml was observed in patients with hematological malignancy (HM) and differed significantly from that observed either in solid organ transplants (3,473 pg/ml) or in patients with autoimmune or inflammatory disorder (3,480 pg/ml). Indeed, the sensitivity of BG assay was estimated at 0.64 (95% CI: 0.35–0.85) in HM patients and was lower than the one observed in the whole PCP group. Furthermore, BG level and fungal burden correlated poorly among all PCP patients.Conclusion: BG is not a reliable biomarker for ruling out PCP in HIV-negative patients with HM. Interpretation of a negative BG result should take into account, but not be limited to, the underlying condition predisposing to PCP.

Toxoplasmosis, cryptosporidiosis, and isosporiasis in HIV-negative immunocompromised patients: A single-centre study, Ottawa, Ontario, Canada

Historically, patients with HIV have been at the highest risk of infection with opportunistic protozoans such as Toxoplasma, Cryptosporidium, and Isospora. Among patients with HIV who are compliant with antiretroviral therapy, the likelihood of acquiring an opportunistic infection is low. The risk of infection is harder to mitigate in the growing number of HIV-negative immunodeficient patients, such as people with hematological malignancies or those who are post-transplantation. We conducted a retrospective case series of patients with documented Toxoplasma infections between 2008 and 2017 and with Cryptosporidium and Isospora infections between 2014 and 2017 at the Ottawa Hospital. During the study period, there were 10 confirmed cases of toxoplasmosis, 20 cases of cryptosporidiosis, and 2 cases of isosporiasis. Cryptosporidiosis (95%) and toxoplasmosis (60%) occurred more frequently among HIV-negative patients, whereas isosporiasis cases were limited to HIV-positive patients. Among patients with cryptosporidiosis, the most common underlying cause of immunosuppression in HIV-negative individuals was solid organ transplantation (15.79%), followed by diabetes (10.53%), end-stage renal disease (5.26%), and hematologic malignancy (5.26%). Seventy percent of patients had no known cause of immunosuppression. The most common underlying condition associated with toxoplasmosis was hematological malignancy (50%), followed by solid organ transplantation (33.33%), and solid tumours (16.66%). This study's results suggest that Cryptosporidium infections are more common among immunocompetent patients in Ottawa, whereas Toxoplasma infections are more common among HIV-negative patients with acquired immunodeficiencies. As the demographics of immunocompromised individuals continue to evolve, screening for protozoal infections in high-risk populations may become clinically important.

Pneumocystis pneumonia in HIV-negative immunocompromised patients in Internal Medicine ward

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection typically observed in AIDS patients, for whom it represents a leading cause of death. However, its incidence among HIV-negative immunocompromised patients is progressively increasing, with a significantly higher mortality compared to that of AIDS-patients. We performed a retrospective observational study on HIV-negative patients with PJP. We aimed to determine their epidemiological features and their biohumoral and therapeutic variables, searching for a correlation between them and our patients’ outcome. We included all patients admitted to our Internal Medicine ward from January 2010 to June 2015, who were immunocompromised at the time of admission and had microbiologically confirmed PJP (association between compatible clinical-radiological findings and qualitative polymerase chain reaction positivity on bronchoalveolar lavage). Their immune impairment was assessed considering both their medical history and their complete white blood cells (WBC), differential WBC and their CD4 cell count. Transfer to Intensive Care Unit (ICU) or death was considered as an unfavorable clinical outcome, while hospital discharge or transfer to a non-ICU ward was considered as a favorable outcome. We included a total of 18 patients in our statistical analysis. We used Student’s t-test and Fischer’s χ-square test to compare, respectively, normally distributed continuous variables and non-continuous variables. Our patients’ mean age was 65±13.9 years. All of them had cancer, mostly hematological malignancies (13/18), notably non-Hodgkin lymphoma (NHL; 8/13). They were all being or had been recently treated with chemotherapy (10/18) and/or high-dose glucocorticoids, with full dose or during tapering (13/18). Statistical analysis of blood tests results showed a significant difference between mean serum lactate dehydrogenase (LDH) concentration in the group of patients with favorable vs unfavorable outcome. Also, mean serum immunoglobulins G (IgG) concentration and certain arterial blood gas findings (mean arterial paO2/FiO2, mean blood Ph and mean paCO2) at the time of admission were significantly different in the two groups of patients. 12/18 patient’s outcome turned out unfavorable. Trimethoprim + sulfamethoxazole (TMP+SMX) treatment was given to all our patients, with a mean duration of 13.39±9.36 days. Patients with a favorable outcome had received TMP+SMX treatment significantly earlier than those with an unfavorable outcome. Hematological malignancies, according to literature, confer the strongest predisposition to PJP. Both chemotherapy and high-dose Glucocorticoid treatment are well known predisposing factors. A remarkable elevation of serum LDH represents both a typical clinical feature and a well-known negative prognostic factor in PJP. Low IgG levels have never been reported as a negative prognostic factor, but their role in enhancing macrophage killing of pneumocystis may account for the worst observed prognosis in the group of patients with lower mean levels. Therefore, in order to reduce the heavy mortality rate associated with PJP, an early beginning of specific treatment is of utmost importance, and even if this is certainly true for many infectious diseases, the time gap is particularly limited in the setting of this type of pneumonia. Hence, PJP should be ruled out as soon as possible and, in case of a strong clinical- radiological suspicion, therapy should be started immediately, even while waiting for microbiological confirmation (especially in critically-ill patients).

Gomori Methenamine Silver Stain on Bronchoalveolar Lavage Fluid Is Poorly Sensitive for Diagnosis of Pneumocystis jiroveci Pneumonia in HIV-Negative Immunocompromised Patients and May Lead to Missed or Delayed Diagnoses.

Direct visualization of Pneumocystis jiroveci organisms, using Gomori methenamine silver (GMS) staining in bronchoalveolar lavage fluid (BAL), is a historical gold standard that has been widely used for the diagnosis of P jiroveci pneumonia (PJP). However, the stain may be less sensitive in human immunodeficiency virus (HIV)-negative immunocompromised patients owing to a lower burden of organisms. To assess the sensitivity of the GMS stain on BAL fluid for the diagnosis of PJP in HIV-negative immunocompromised patients as compared to HIV-positive patients. We conducted a retrospective review from 2012 to 2018 to identify immunocompromised patients (≥18 years old) who underwent bronchoscopy with BAL GMS staining for the diagnosis of PJP. To assess for sensitivity, we sought to identify BAL GMS-positive cases and BAL GMS-negative cases of PJP. The BAL GMS-negative cases were categorized into proven and probable PJP. We identified 45 adult immunocompromised patients with proven and probable PJP, including 24 HIV-negative (11 BAL GMS-positive and 13 BAL GMS-negative) and 21 HIV-positive cases (all were BAL GMS-positive). The sensitivity of BAL GMS for the diagnosis of PJP in HIV-negative immunocompromised patients was 11 of 24 (46%) versus 21 of 21 (100%) in HIV-positive patients (CD4: median, 10 cells/mL; range, 3-300 cells/mL). Delayed or missed diagnoses were seen in 3 cases of BAL GMS-negative PJP. Re-examination of BAL GMS slides showed rare P jiroveci cysts in 1 case. BAL GMS has poor sensitivity for PJP in HIV-negative immunocompromised patients. Using BAL GMS as a sole method for PJP may result in missed or delayed diagnoses in this population.

A Comparison of the Clinical Characteristics and Outcomes of Cryptococcal Meningitis in HIV-negative Individuals With and Without Immunosuppression.

Cryptococcal meningitis (CM) is found to occur in immunosuppressed patients and those who are immunocompetent. This study aimed to compare the presentation and outcome of CM in patients who are human immunodeficiency virus (HIV) negative with and without immunosuppression. We reviewed 255 clinical records from patients with CM who are HIV negative. The demographic and clinical characteristics, cerebrospinal fluid profiles, brain magnetic resonance imaging, treatment, and outcomes of these individuals were retrospectively analyzed. Among the 255 patients with CM, 91 (35.7%) appeared immunocompetent. CM was present in a younger population in the immunocompetent group (above 50 y, 19.8% vs. 32.3%, P=0.026), with higher initial complaints of visual and auditory symptoms (45.1% vs. 27.4%, P=0.004; 19.8% vs. 9.1%, P=0.016; respectively) and higher cerebrospinal fluid white blood cell counts (30.8% vs. 45.1%, P=0.009) compared with the immunocompromised patients. In addition, the immunocompetent patients had a higher proportion of normal brain images than did the immunocompromised patients (10% vs. 2%, P=0.028). There were no differences in hospital mortality and satisfactory outcomes between the groups (mortality: 10.9% vs. 7.0%, P=0.416; satisfactory outcomes: 76.4% vs. 80.2%, P=0.585). We found significant differences between the immunocompetent and HIV-negative immunocompromised patients; however, there were fewer differences between the groups than expected. Further studies assessing the immune responses in both groups should be performed.

2566. Diagnosis of Pneumocystis jiroveci Pneumonia in HIV-Negative Immunocompromised Patients: Is the Gomori-Methenamine Silver Stain of Bronchoalveolar Lavage Fluid the Gold Standard or Sub-Standard?

BackgroundDirect visualization of Pneumocystis jiroveci on bronchoalveolar lavage (BAL) fluid using the Gomori-methenamine-silver (GMS) stain historically has been the mainstay of diagnosis for P. jiroveci pneumonia (PJP), with studies from the early HIV/AIDS era reporting sensitivities of 90–95%. However, the burden of P. jiroveci organisms in BAL fluid is significantly lower in HIV-negative immunocompromised patients compared with HIV-positive patients with PJP, raising concerns that the BAL GMS stain is less sensitive in this population.MethodsWe conducted a retrospective observational study at Yale-New Haven Hospital from 2012 to 2018, using electronic medical record chart reviews, to identify patients who underwent bronchoscopy with BAL GMS stain for the diagnosis of PJP. We collected additional patient factors such as age, sex, HIV status, and immunosuppressed status. For patients with a negative BAL GMS stain, we collected data on other diagnostics, including positive GMS lung biopsies, positive PJP PCR or DFA, and elevated serum (1–3)-β-d-glucan levels. We defined BAL GMS-negative cases as proven or probable based on investigator generated criteria (see Figure 1).ResultsWe identified 52 patients with PJP who received a BAL GMS stain, including 28 HIV-positive and 24 HIV-negative cases. Of 24 HIV-negative cases, 11 had BAL GMS-positive PJP and 13 had BAL GMS-negative PJP (9 proven and 4 probable). In the latter group, 6 had hematologic malignancies (HM), 2 had solid-organ transplants (SOT), 1 had hematopoietic stem cell transplant, 2 had SOT plus HM, and 2 received high-dose steroids. Proven diagnoses were made by GMS-positive lung biopsy (n = 6), DFA (n = 2), and PCR (n = 1). Elevated (1–3)-β-d-glucan was observed in 7 of 8 cases (median: >500 pg/mL; range 39 to >500). Three patients developed adverse outcomes (1 readmission due to untreated PJP and 2 treatment delays). BAL GMS sensitivity for HIV-negative patients was 11/24 (46%) vs. 28/28 (100%) in HIV-positive patients.ConclusionThe sensitivity of BAL GMS for PJP is poor in HIV-negative immunocompromised patients. Missed cases or delayed treatment for PJP may lead to adverse outcomes. In HIV-negative patients with a clinical syndrome compatible with PJP, a negative BAL GMS does not rule out PJP and must be confirmed by supplementary diagnostics.Figure 1Disclosures All authors: No reported disclosures.

Treatment of cryptococcosis in non-HIV immunocompromised patients.

Cryptococcosis has become a common opportunistic infection among non-HIV immunocompromised hosts. Recent reports have shown the incidence of Cryptococcosis among HIV-negative immunocompromised patients reaches close to half of the overall cases reported in the USA. Management of this infection in this population carries unique challenges. We aim to review relevant and recent research findings to develop treatment recommendations for this type of population. Most of the recommendations for the management of non-HIV immunocompromised host are extrapolated from HIV studies. Cryptococcosis among non-HIV patients is common but often overlooked. Some clinical factors, when present, may increase the risk of Cryptococcosis among HIV-negative patients and appropriate screening and assessment for the disease is necessary. Treating clinicians should consider a longer duration of induction with Amphotericin B depending on the type of host, immunocompromised state, antifungal response and presence of neurological complications. Baseline fluconazole resistance can reach up to 12%, which is an important consideration for cryptococcal meningitis relapses or suboptimal responses to therapy. Cryptococcus spp. conveys a high disease burden among immunocompromised hosts. Clinicians must consider numerous variables and factors in a dynamic way to offer the best possible treatment and to monitor their response to therapy. Due to the high cost and associated toxicities, we still need new affordable therapies and studies among non-HIV immunocompromised patients.

Immune reconstitution inflammatory syndrome in non-HIV immunosuppressed patients.

Immune reconstitution inflammatory syndrome (IRIS) represents a clinical phenomenon of immune-mediated inflammation against various antigens, including pathogenic microorganisms, drugs and unknown autoantigens, during recovery from immunosuppressed conditions. IRIS has become well recognized in HIV-infected populations. However, IRIS has seldom been recognized in HIV-negative immunocompromised patients. In the last 15 years, the immunopathogenesis of drug-induced hypersensitivity syndrome (DIHS) has been largely determined. Laboratory data and clinical observations support the idea that DIHS represents a prototype of non-HIV IRIS. Primary diseases in which non-HIV IRIS is secondary include severe cutaneous adverse drug reactions, such as DIHS, autoimmune diseases, collagen diseases, pregnancy and internal malignancies. Potential triggers of recovery from an immune deterioration state include a discontinuation or abrupt tapering of systemic steroids and/or immunosuppressants, withdrawal or reduced effects of anti-tumor necrosis factor-α antibodies, and the use of immune-checkpoint antagonists for the advanced stages of malignancies. Wide use of IRIS across large populations risks oversimplification but highlights a key unifying principle. Balanced sensitivity and specificity for its diagnostic criteria and classification are necessary for the establishment of clinical practice guidelines for non-HIV IRIS. Additionally, the development of a useful combination of biomarkers is currently an urgent issue.

Infectious disease ward admission positively influences P. jiroveci pneumonia (PjP) outcome: A retrospective analysis of 116 HIV-positive and HIV-negative immunocompromised patients.

P. jiroveci (Pj) causes a potentially fatal pneumonia in immunocompromised patients and the factors associated with a bad outcome are poorly understood. A retrospective analysis on Pj pneumonia (PjP) cases occurring in Tor Vergata University Hospital, Italy, during the period 2011–2015. The patients’ demographic, clinical and radiological characteristics and the Pj genotypes were considered. The study population included 116 patients, 37.9% of whom had haematological malignancy or underwent haematological stem cell transplantation (HSCT), 22.4% had HIV infection, 16.4% had chronic lung diseases (CLD), 7.8% had a solid cancer, and 3.4% underwent a solid organ transplant (SOT). The remaining 12.1% had a miscellaneous other condition. At univariate analysis, being older than 60 years was significantly correlated with a severe PjP (OR [95%CI] 2.52 [0.10–5.76]; p = 0.031) and death (OR [95%CI] 2.44 [1.05–5.70]; p = 0.036), while a previous trimethoprim/sulfamethoxazole (TMP/SMX) prophylaxis were significantly associated with a less severe pneumonia (OR[95%CI] 0.35 [0.15–0.84], p = 0.023); moreover, death due to PjP was significantly more frequent in patients with CLD (OR[95%CI] 3.26 [1.17–9.05]; p = 0.019) while, admission to the Infectious Diseases Unit was significantly associated with fewer deaths (OR[95%CI] 0.10 [0.03–0.36], p = 0.002). At multivariate analysis, a better PjP outcome was observed in patients taking TMP/SMX prophylaxis and that were admitted to the Infectious Diseases Unit (OR[95%CI] 0.27 [0.07–1.03], p = 0.055, OR[95%CI] 0.16 [0.05–0.55]; p = 0.004, respectively).In conclusion, in our study population, TMP/SMX prophylaxis and infectious disease specialist approach were variables correlated with a better PjP outcome.

Utility of urine lipoarabinomannan (LAM) in diagnosing tuberculosis and predicting mortality with and without HIV: prospective TB cohort from the Thailand Big City TB Research Network

To evaluate the applicability and accuracy of the urine lipoarabinomannan (LAM) test in tuberculosis (TB)/HIV co-infected patients and HIV-negative patients with disseminated TB. Frozen urine samples obtained at baseline from patients in the TB research cohort with proven culture-positive TB were selected for blinded urine LAM testing. One hundred and nine patients were categorized into four groups: (1) HIV-positive patients with TB; (2) HIV-negative patients with disseminated TB; (3) HIV-negative immunocompromised patients with TB; and (4) patients with diseases other than TB. The sensitivity of urine LAM testing for culture-positive TB, specificity of urine LAM testing for patients without TB, positive predictive value (PPV), and negative predictive value (NPV) were assessed. The sensitivity of the urine LAM test in group 1 patients with a CD4 T-cell count of >100, ≤100, and ≤50 cells/mm3 was 38.5%, 40.6%, and 45%, respectively. The specificity and PPV of the urine LAM test were >80%. The sensitivity of the test was 20% in group 2 and 12.5% in group 3, and the specificity and PPV were 100% for both groups. A positive urine LAM test result was significantly associated with death. This promising diagnostic tool could increase the yield of TB diagnosis and may predict the mortality rate of TB infection, particularly in TB/HIV co-infected patients.

Molecular diagnosis of toxoplasmosis in immunocompromised patients: a 3-year multicenter retrospective study.

Toxoplasmosis is a life-threatening infection in immunocompromised patients (ICPs). The definitive diagnosis relies on parasite DNA detection, but little is known about the incidence and burden of disease in HIV-negative patients. A 3-year retrospective study was conducted in 15 reference laboratories from the network of the French National Reference Center for Toxoplasmosis, in order to record the frequency of Toxoplasma gondii DNA detection in ICPs and to review the molecular methods used for diagnosis and the prevention measures implemented in transplant patients. During the study period, of 31,640 PCRs performed on samples from ICPs, 610 were positive (323 patients). Blood (n = 337 samples), cerebrospinal fluid (n = 101 samples), and aqueous humor (n = 100 samples) were more frequently positive. Chemoprophylaxis schemes in transplant patients differed between centers. PCR follow-up of allogeneic hematopoietic stem cell transplant (allo-HSCT) patients was implemented in 8/15 centers. Data from 180 patients (13 centers) were further analyzed regarding clinical setting and outcome. Only 68/180 (38%) patients were HIV(+); the remaining 62% consisted of 72 HSCT, 14 solid organ transplant, and 26 miscellaneous immunodeficiency patients. Cerebral toxoplasmosis and disseminated toxoplasmosis were most frequently observed in HIV and transplant patients, respectively. Of 72 allo-HSCT patients with a positive PCR result, 23 were asymptomatic; all were diagnosed in centers performing systematic blood PCR follow-up, and they received specific treatment. Overall survival of allo-HSCT patients at 2 months was better in centers with PCR follow-up than in other centers (P < 0.01). This study provides updated data on the frequency of toxoplasmosis in HIV-negative ICPs and suggests that regular PCR follow-up of allo-HSCT patients could guide preemptive treatment and improve outcome.

Pneumocystis jirovecii dihydropteroate synthase gene mutations in a group of HIV-negative immunocompromised patients with Pneumocystis pneumonia.

The purpose of this study was to investigate dihydropteroate synthase (DHPS) mutations and their clinical context in non-HIV-infected patients with Pneumocystis pneumonia (PCP). DHPS genes in respiratory samples collected from HIV-negative patients with PCP presented between January 2008 and April 2011 were amplified by polymerase chain reaction (PCR) and sequenced. Basic clinical data from the medical records of the patients were also reviewed. The most common point mutations, which result in Thr55Ala and Pro57Ser amino acid substitutions, were not detected in the Pneumocystis jirovecii sampled from the HIV-negative patients. Two other point mutations, which result in nonsynonymous mutation, Asp90Asn and Glu98Lys, were identified in P. jirovecii from two patients. Among the patients, the levels of lactate dehydrogenase (LDH), C-reactive protein (CRP) and plasma (1–3) β-D-glucan were elevated in 75, 92.31 and 42.86% of patients, respectively. The percentage of circulating lymphocytes was significantly lower in non-survivors than in survivors [4.2%, interquartile range (IQR) 2.4–5.85 versus 10.1%, IQR 5.65–23.4; P=0.019]. The neutrophil proportion in bronchoalveolar lavage fluid (BALF) was significantly higher in non-survivors than in survivors (49.78±27.67 versus 21.33±15.03%; P=0.047). Thirteen patients had received adjunctive corticosteroids (1 mg/kg/day prednisone equivalent) and nine (69.23%) of them eventually experienced treatment failure. No common DHPS gene mutations of P. jirovecii were detected in the HIV-negative PCP patients. However, other mutations did exist, the significance of which remains to be further identified. The elevation of neutrophil counts in BALF and reduction of the number of lymphocytes in peripheral blood may be associated with poor outcome. The efficacy of adjunctive steroid therapy in HIV-negative patients with P. jirovecii infection requires further investigation.

Outcome of Pneumocystis jirovecii pneumonia diagnosed by polymerase chain reaction in patients without human immunodeficiency virus infection

Pneumonia caused by Pneumocystis jirovecii (PCP) in patients without human immunodeficiency virus (HIV) infection is associated with high mortality. The diagnosis of PCP at our institution is based on detection of DNA using a polymerase chain reaction (PCR) assay. The aim of this study was to describe the clinical manifestations, outcomes and factors associated with mortality due to PCP, as diagnosed by PCR, in patients without HIV infection. Over a 6-year period, all HIV-negative immunocompromised patients suspected of having an opportunistic pulmonary infection underwent diagnostic bronchoscopy. A multigene PCR assay that detects Pneumocystis jirovecii DNA was used for the diagnosis of PCP. Patients were considered to have PCP if they had underlying immunodeficiency, compatible signs and symptoms, abnormal radiological findings, and Pneumocystis jirovecii DNA was detected in a bronchoalveolar lavage fluid sample. Data was collected retrospectively. PCP was diagnosed in 58 patients. The underlying conditions included haematological malignancies (60.3%), solid tumours (17.2%) and immunosuppressive treatment (22.4%). The most common clinical features in patients with PCP were fever (94.6%), dyspnoea (67.2%) and cough (36.2%). The overall in-hospital mortality was 17.2% (10/58). Mortality was associated with co-infections, high lactate dehydrogenase levels, female gender, and higher pneumonia severity index and acute physiology and chronic health evaluation III scores. In this study, the mortality of HIV-negative patients with PCP was low compared with previous reports. We hypothesize that this finding resulted from the increased sensitivity of a PCR-based assay, as compared with traditional methods, for the diagnosis of PCP in HIV-negative patients.

Alveolar and Blood T Lymphocyte Profiles in Pneumocystis jirovecii–Positive Patients: Effects of HIV Status

There are substantial differences in the risk evaluation, clinical presentation, and outcome of Pneumocystis pneumonia between human immunodeficiency virus (HIV)-positive and HIV-negative immunocompromised patients. To compare the host immune defenses against Pneumocystis jirovecii, the blood and alveolar lymphocyte profile was explored in these 2 populations. The total, CD3(+), CD4(+), and CD8(+) T-lymphocyte counts were measured in the blood and alveoli of immunocompromised patients with a P. jirovecii DNA detected in their bronchoalveolar lavage samples, according to their HIV status. In blood and alveoli, the CD4(+) and CD8(+) T-lymphocyte counts were higher and lower, respectively, in the HIV-negative group. The threshold for initiating prophylaxis in HIV-positive persons, 200 CD4(+) T cells/μL, was not pertinent for HIV-negative patients. The P. jirovecii burden correlated with the blood CD4(+) T-cell counts in the HIV-positive but not in the HIV-negative group. Nevertheless, whatever the HIV status, a correlation was observed between alveolar CD4(+) T cells and the P. jirovecii burden. The T-lymphocyte profile was different between HIV-positive and HIV-negative patients with P. jirovecii, suggesting a distinct pathogenesis. Alveolar CD4(+) T cells could be critical to explain the development of Pneumocystis pneumonia but may also be important for evaluation of disease risk, mostly among HIV-negative immunocompromised patients.

P253 Pulmonary infiltrates in HIV negative immunocompromised patients: outcome and predictive factors

IntroductionThe incidence of pulmonary complications in immunocompromised patients is on the rise mainly driven by increased organ and bone marrow transplants, more aggressive chemotherapy and novel immunosuppressants.1 Mortality rates in...

Differences and similarities of cytomegalovirus and pneumocystis pneumonia in HIV-negative immunocompromised patients – thin section CT morphology in the early phase of the disease

Differences and similarities of cytomegalovirus and pneumocystis pneumonia in HIV-negative immunocompromised patients – thin section CT morphology in the early phase of the disease

Differences and similarities of cytomegalovirus and pneumocystis pneumonia in HIV-negative immunocompromised patients – thin section CT morphology in the early phase of the disease

The purpose of this study was to assess CT morphology of pneumocystis pneumonia (PcP) and cytomegalovirus (CMV) pneumonia for specific characteristic features, similarities as well as differences, which might contribute to an early diagnosis and, therefore, influence patient management 58 patients were included, 31 with CMV pneumonia and 27 with PcP. All patients with CMV pneumonia had underlying haematological malignancies (n = 31) mainly treated by haematopoietic cell transplantation (HCT) (n = 26). Patients with PcP had haematological malignancies (n = 17) treated by HCT in 6, solid tumours (n = 5) and corticosteroid therapy (n = 5). Thin section CTs were analysed retrospectively by two radiologists. 18 CT morphological criteria were evaluated for presence or absence. Significance was calculated by chi2 test. Interobserver correlation was tested by kappa-statistic (K) Only 5 of the 18 features were found to have significantly different frequencies in the two entities. Apical distribution (p<0.01), mosaic pattern (p<0.01) and homogeneous structure of ground-glass opacities (GGO) (p<0.05) were found more frequently in PcP (each K: 0.7-0.9), whereas small nodules or unsharp demarcation of GGO and consolidation were typical of CMV pneumonia (p<0.05). Peripheral sparing, consolidation and septal thickening inter alia were found equally in both groups In conclusion analysis of craniocaudal distribution, demarcation and structure of infiltrates may be helpful in prioritizing differential diagnosis of CMV pneumonia or PcP. However, some features thought typical for one or the other entities appear with similar frequency in both groups in HIV-negative patients.

Molecular diagnosis of Pneumocystis pneumonia

The detection of Pneumocystis DNA in clinical specimens by using PCR assays is leading to important advances in Pneumocystis pneumonia (PcP) clinical diagnosis, therapy and epidemiology. Highly sensitive and specific PCR tools improved the clinical diagnosis of PcP allowing an accurate, early diagnosis of Pneumocystis infection, which should lead to a decreased duration from onset of symptoms to treatment, a period with recognized impact on prognosis. This aspect has marked importance in HIV-negative immunocompromised patients, who develop often PcP with lower parasite rates than AIDS patients. The specific amplification of selected polymorphous sequences of Pneumocystis jirovecii genome, especially of internal transcribed spacer regions of the nuclear rRNA operon, has led to the identification of specific parasite genotypes which might be associated with PcP severity. Moreover, multi-locus genotyping revealed to be a useful tool to explore person-to-person transmission. Furthermore, PCR was recently used for detecting P. jirovecii dihydropteroate synthase gene mutations, which are apparently associated with sulfa drug resistance. PCR assays detected Pneumocystis-DNA in bronchoalveolar lavage fluid or biopsy specimens, but also in oropharyngeal washings obtained by rinsing of the mouth. This non-invasive procedure may reach 90%-sensitivity and has been used for monitoring the response to treatment in AIDS patients and for typing Pneumocystis isolates.