Pneumocystis carinii pneumonitis in children with malignancies

Pneumocystis jirovecii pneumonia in paediatric acute lymphoblastic leukaemia: A report from the multi-international clinical trial AIEOP-BFM ALL 2009

Pneumocystis jirovecii can cause life-threatening pneumonia (PjP), and patients with haematological malignancies are at high risk of this infection. Prophylactic measures have significantly decreased morbidity and mortality, but there is a paucity of contemporary data on the incidence and clinical course of PjP in well-defined and homogenous patient populations, such as children suffering from acute lymphoblastic leukaemia (ALL). In the multi-international trial AIEOP-BFM ALL2009, PjP was diagnosed in six children (incidence 1/1000) and was associated with insufficient prophylaxis in five of them. Although none of the patients died of PjP, the long-term impact of the infection is unclear.

Metagenomic next-generation sequencing for the diagnosis of Pneumocystis jirovecii Pneumonia in critically pediatric patients

OBJECTIVE

The aim of this study was to evaluate the effectiveness of metagenomic next-generation sequencing (mNGS) for the diagnosis of Pneumocystis jirovecii Pneumonia (PCP) in critically pediatric patients.

METHODS

Seventeen critically pediatric patients with PCP and sixty patients diagnosed with non-PCP pneumonia who were admitted in pediatric intensive care unit between June 2018 and July 2021 were enrolled. Conventional methods and mNGS for detecting Pneumocystis jirovecii (P. jirovecii) were compared. The patients' demographics, comorbidities, laboratory test results, antibiotic treatment response and 30 day mortality were analyzed.

RESULT

The mNGS showed a satisfying diagnostic performance with a sensitivity of 100% in detecting P. jirovecii compared with Gomori methenamine silver staining (5.9%), serum (1,3)-β-D-glucan (86.7%) and and LDH (55.6%). The diagnostic specificity of mNGS for PCP was higher than that of serum BDG (56.7%) and LDH (71.4%). In PCP group, over one thirds' cases had mixed infections. Compared with survivors, non-survivors had higher stringently mapped read numbers (SMRNs) in bronchoalveolar lavage fluid (BALF) sample (P < 0.05), suggesting SMRNs were closely associated with the severity of response. The detection for P. jirovecii by mNGS both in BALF and blood samples reached a concordance rate of 100%, and the SMRNs in the BALF were remarkably higher than that in blood samples. Initial antimicrobial treatment was modified in 88.2% of PCP patients based on the mNGS results.

CONCLUSION

The mNGS is a potential and efficient technology in diagnosing PCP and shows a satisfying performance in the detection of co-pathogens. Both blood and BALF samples for mNGS are suggested for the presumptive diagnosis of PCP.

UK paediatric oncology Pneumocystis jirovecii pneumonia surveillance study

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is a serious infective complication of immunosuppressive therapy. There are insufficient data concerning the incidence or mortality rate in children undergoing treatment for malignancies and how these may be influenced by prophylaxis.

OBJECTIVE

Prospective collection of clinical information for all suspected and proven cases of PJP in children with cancer in the UK and Ireland.

DESIGN

A surveillance survey was undertaken using a key contact at each paediatric oncology Principle Treatment Centre (PTC).

MAIN OUTCOME MEASURES

To describe the mortality, outcomes and use of prophylaxis in this at-risk group.

RESULTS

The study confirms that PJP is rare, with only 32 cases detected in the UK over a 2-year period reported from all 20 PTCs. No deaths were directly attributed to PJP, in contrast to previously reported high mortality rates. Breakthrough infection may occur despite prescription of ostensibly adequate prophylaxis with co-trimoxazole; 11 such cases were identified. Six infections occurred in patients for whom prophylaxis was not thought to be indicated. Two infections occurred in patients for whom prophylaxis was specifically omitted due to concerns about potential bone marrow suppression or delayed engraftment.

CONCLUSION

PJP in children treated for malignant disease is rare. Breakthrough infection despite prophylaxis with co-trimoxazole may represent pathogen resistance or non-compliance. Further consideration of the use of PJP prophylaxis during acute myeloid leukaemia and non-Hodgkin's lymphoma treatment is warranted, alongside appraisal of the clinical implications of the possible marrow suppressive effects of co-trimoxazole and its interactions with methotrexate.

Primary prophylaxis of bacterial infections and Pneumocystis jirovecii pneumonia in patients with hematologic malignancies and solid tumors: 2020 updated guidelines of the Infectious Diseases Working Party of the German Society of Hematology and Medical Oncology (AGIHO/DGHO)

Hematologic and oncologic patients with chemo- or immunotherapy-related immunosuppression are at substantial risk for bacterial infections and Pneumocystis jirovecii pneumonia (PcP). As bacterial resistances are increasing worldwide and new research reshapes our understanding of the interactions between the human host and bacterial commensals, administration of antibacterial prophylaxis has become a matter of discussion. This guideline constitutes an update of the 2013 published guideline of the Infectious Diseases Working Party (AGIHO) of the German Society for Hematology and Medical Oncology (DGHO). It gives an overview about current strategies for antibacterial prophylaxis in cancer patients while taking into account the impact of antibacterial prophylaxis on the human microbiome and resistance development. Current literature published from January 2012 to August 2020 was searched and evidence-based recommendations were developed by an expert panel. All recommendations were discussed and approved in a consensus conference of the AGIHO prior to publication. As a result, we present a comprehensive update and extension of our guideline for antibacterial and PcP prophylaxis in cancer patients.

Pneumocystis jirovecii Pneumonia in Children with Hematological Malignancies: Diagnosis and Approaches to Management

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infection that mostly affects children with suppressed cellular immunity. PJP was the most common cause of infectious death in children with acute lymphoblastic leukemia prior to the inclusion of cotrimoxazole prophylaxis as part of the standard medical care in the late 1980s. Children with acute leukemia, lymphomas, and those undergoing hematopoietic stem cell transplantation, especially allogeneic transplantation, are also at high risk of PJP. Persistent lymphopenia, graft versus host disease, poor immune reconstitution, and lengthy use of corticosteroids are significant risk factors for PJP. Active infection may be due to reactivation of latent infection or recent acquisition from environmental exposure. Intense hypoxemia and impaired diffusing capacity of the lungs are hallmarks of PJP, while computerized tomography of the lungs is the diagnostic technique of choice. Immunofluorescence testing with monoclonal antibodies followed by fluorescent microscopy and polymerase chain reaction testing of respiratory specimens have emerged as the best diagnostic methods. Measurement of (1-3)-β-D-glucan in the serum has a high negative predictive value in ruling out PJP. Oral cotrimoxazole is effective for prophylaxis, but in intolerant patients, intravenous and aerosolized pentamidine, dapsone, and atovaquone are effective alternatives. Ιntravenous cotrimoxazole is the treatment of choice, but PJP has a high mortality even with appropriate therapy.

Diagnosing Pneumocystis jirovecii pneumonia: A review of current methods and novel approaches

Pneumocystis jirovecii can cause life-threatening pneumonia in immunocompromised patients. Traditional diagnostic testing has relied on staining and direct visualization of the life-forms in bronchoalveolar lavage fluid. This method has proven insensitive, and invasive procedures may be needed to obtain adequate samples. Molecular methods of detection such as polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), and antibody-antigen assays have been developed in an effort to solve these problems. These techniques are very sensitive and have the potential to detect Pneumocystis life-forms in noninvasive samples such as sputum, oral washes, nasopharyngeal aspirates, and serum. This review evaluates 100 studies that compare use of various diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) in patient samples. Novel diagnostic methods have been widely used in the research setting but have faced barriers to clinical implementation including: interpretation of low fungal burdens, standardization of techniques, integration into resource-poor settings, poor understanding of the impact of host factors, geographic variations in the organism, heterogeneity of studies, and limited clinician recognition of PCP. Addressing these barriers will require identification of phenotypes that progress to PCP and diagnostic cut-offs for colonization, generation of life-form specific markers, comparison of commercial PCR assays, investigation of cost-effective point of care options, evaluation of host factors such as HIV status that may impact diagnosis, and identification of markers of genetic diversity that may be useful in diagnostic panels. Performing high-quality studies and educating physicians will be crucial to improve the rates of diagnosis of PCP and ultimately to improve patient outcomes.

Pneumocystis jirovecii pneumonia in children. A retrospective study in a single center over three decades

INTRODUCTION

Pneumocystis jirovecii pneumonia (PJP) is a life-threatening condition in immunocompromised children. Our aim is to analyze the epidemiologic and clinical characteristics of PJP cases in our setting, describing the prognosis and related risk factors.

METHODS

Retrospective study including all pediatric patients (≤18 years) with PJP admitted to our hospital (January 1989-December 2016). Case definition: patient with acute pneumonitis and P.jirovecii detection in bronchoalveolar lavage or tracheal aspirate using methenamine silver or direct antibody fluorescence staining, or Real-Time Polymerase Chain Reaction.

RESULTS

Twenty-five cases (0.9 cases/year) were identified. Median age was 2.2 years (interquartile range: 0.5-12.3), 64% were male, and 12% were receiving appropriate antimicrobial prophylaxis. Cytomegalovirus coinfection was detected in 26% cases. The most common underlying diseases were primary immunodeficiencies (36%) and 16% were human immunodeficiency virus (HIV)-infected children. Eighteen were admitted to the pediatric intensive care unit (PICU) and overall 30-day mortality was 20% (31.25% in HIV non-infected vs 0% in HIV-infected patients; OR: 0.33, 95% CI: 0.02-7.24, p=0.55). Clinical outcome was worse in girls and those patients requiring adjuvant steroid therapy. HIV non-infected patients, higher initial LDH, younger age and shorter time elapsed between diagnosis of PJP and the underlying disease were identified as risk factors to be admitted to the PICU (p=0.05, p=0.026, p=0.04 and p=0.001 respectively).

CONCLUSION

Accompanying the widespread use of combined antiretroviral therapy, PJP has been diagnosed almost exclusively in HIV non-infected children at our institution. Moreover, significant higher morbidity rates associated with PJP are seen in this group of patients.

Pentamidine for Prophylaxis against Pneumocystis jirovecii Pneumonia in Pediatric Oncology Patients Receiving Immunosuppressive Chemotherapy

Pneumocystis jirovecii pneumonia is a life-threatening opportunistic infection in children receiving immunosuppressive chemotherapy. Without prophylaxis, up to 25% of pediatric oncology patients receiving chemotherapy will develop Pneumocystis jirovecii pneumonia. Trimethoprim-sulfamethoxazole is the preferred agent for prophylaxis against Pneumocystis jirovecii pneumonia. Pentamidine may be an acceptable alternative for pediatric patients unable to tolerate trimethoprim-sulfamethoxazole. A retrospective review was conducted of pediatric oncology patients who received ≥1 dose of pentamidine for Pneumocystis jirovecii pneumonia prophylaxis between January 2007 and August 2014. Electronic medical records were reviewed to determine the incidence of breakthrough Pneumocystis jirovecii pneumonia or discontinuation of pentamidine associated with adverse events. A total of 754 patients received pentamidine prophylaxis during the period. There were no cases of probable or proven Pneumocystis pneumonia, and 4 cases (0.5%) of possible Pneumocystis pneumonia. The incidence of possible breakthrough Pneumocystis pneumonia was not significantly different between subgroups based on age (<12 months [1.7%] versus ≥12 months [0.4%], P = 0.3), route of administration (aerosolized [0%] versus intravenous [1.0%], P = 0.2), or hematopoietic stem cell transplant status (transplant [0.4%] versus no transplant [0.8%], P = 0.6). Pentamidine was discontinued due to an adverse drug event in 23 children (3.1%), more frequently for aerosolized than for intravenous administration (7.6% versus 2.2%, respectively, P = 0.004). Intravenous or inhaled pentamidine may be a safe and effective second-line alternative for prophylaxis against Pneumocystis jirovecii pneumonia in children with cancer receiving immunosuppressive chemotherapy or hematopoietic stem cell transplantation.

The Effect of Ophthalmic Artery Chemosurgery on Immune Function in Retinoblastoma Patients: A Single Institution Retrospective Analysis

BACKGROUND

Ophthalmic artery chemosurgery (OAC) is associated with grade 3 and 4 neutropenia, however the effect on T-cell number and function is unknown. The purpose of this retrospective review was to confirm that patients treated with OAC do not develop immunosuppression warranting Pneumocystis pneumonia prophylaxis.

PROCEDURE

IRB approval was obtained for a single center retrospective review of immune function tests in retinoblastoma patients who received OAC.

RESULTS

Twenty-three patients received ≥3 cycles of OAC and had immune function testing (absolute CD4 count) performed at a median of 34 days postcompletion of therapy (range, 15 to 63 d). Only 1 patient had a low absolute CD4 count of 189 cells/μL (normal, 359 to 1570 cells/μL) 2 and a half months after IV carboplatin and 28 days after their third dose of OAC. This patient was found to have coexisting hypogammaglobulinemia. Repeat immune function testing normalized through continued OAC treatment.

CONCLUSIONS

Clinically significant immune suppression appears rare following OAC alone, but patients previously treated with IV chemotherapy may be immunosuppressed and may benefit from pneumocystis pneumonia prophylaxis until the CD4 count recovers.

Guidelines for the Prophylaxis of Pneumocystis jirovecii Pneumonia (PJP) in Children With Solid Tumors

Although it is well-established that children undergoing allogeneic stem cell transplants and treatment for leukemia should be offered prophylaxis against Pneumocystis jirovecii pneumonia, the risk for children with solid malignancies is less certain. This guideline has been developed with the aim of standardizing practice and optimizing the benefit versus risk of prophylactic medication in this group of patients. P. jirovecii pneumonia has a high mortality rate even with prompt antimicrobial treatment. Since prophylaxis with co-trimoxazole is safe, effective, and inexpensive, we suggest that all children with malignancies undergoing immunosuppressive therapy are offered prophylaxis unless there are clear contraindications.

Pneumocystis Carinii Pneumonia in Adult Non-HIV Disorders

Pneumocystis carinii pneumonia (PCP) remains a serious infection in the immunocompromised host (in the absence of HIV infection) and presents significant management and diagnostic challenges to ICU physicians. Non-HIV PCP is generally abrupt in onset, and follows a fulminate course with high rates of hospitalization, ICT admission, respiratory failure, and requirement for intubation. Mortality is generally high, especially if mechanical ventilation is required. Non-invasive ventilatory support may be considered, although the rapid progression to respiratory failure often necessitates intubation at the time of presentation. Bronchoscopy is often required to establish the diagnosis, and empirical antimicrobial treatment specifically targeted to P. carinii should be initiated while awaiting confirmation. Adjunctive corticosteroids may accelerate recovery, although their use has not yet been established in non-HIV PCP. For the ICU physicians to diagnose PCP, the non-specific presentation of an acute febrile illness and respiratory distress with diffuse pulmonary infiltrates requires a high clinical index of suspician, familiarity with clinical conditions associated with increased risk for PCP, and a low threshold for bronchoscopy to establish the diagnosis.

Pneumocystis jirovecii pneumonia: still a concern in patients with haematological malignancies and stem cell transplant recipients

The risk of patients with ALL and recipients of an allogeneic HSCT developing Pneumocystis jirovecii pneumonia is sufficiently high to warrant guidelines for the laboratory diagnosis, prevention and treatment of the disease. In this issue, the European Conference on Infections in Leukemia (ECIL) presents its recommendations in three companion papers.

A protracted course of Pneumocystis pneumonia in the setting of an immunosuppressed child with GMS-negative bronchoalveolar lavage

We report a case of Pneumocystis pneumonia in a 5-year-old male with Trisomy 21 and acute lymphoblastic leukemia. The lack of response to trimethoprim-sulfamethoxazole raised concerns for antimicrobial resistance. Further, diagnosis of Pneumocystis in this patient was complicated by a GMS-negative bronchoalveolar lavage despite molecular evidence of Pneumocystis infection.

Prophylaxis for Pneumocystis jiroveci pneumonia: is it a necessity in pulmonary patients on high-dose, chronic corticosteroid therapy without AIDS?

The benefit of prophylaxis for Pneumocystis jirovecii pneumonia (PJP) is well documented in immunocompromised patients, particularly those with HIV and/or AIDS; therefore, guidelines dictate this as standard of care. However, there is a paucity of literature regarding those without HIV and/or AIDS who are potentially predisposed to PJP, including patients with sarcoidosis, cryptogenic organizing pneumonia, interstitial lung disease, asthma and chronic obstructive pulmonary disease, who may require high dose of prolonged corticosteroids for disease maintenance or to prevent relapses. In this review, the authors examine the available literature regarding prophylaxis in these groups, elaborate on the pathogenesis of PJP, when to suspect PJP in these patients, as well as explore current recommendations that guide clinical practice regarding implementation of PJP prophylaxis, namely with trimethoprim/sulfamethoxazole being the preferred agent. In summary, the role of PJP prophylaxis in non-HIV patients on chronic steroids remains controversial. The authors present a review of the literature to provide better guidance to the clinician regarding the need to initiate PJP prophylaxis in this patient population.

Incidence of Pneumocystis jiroveci pneumonia among groups at risk in HIV-negative patients

BACKGROUND

Pneumocystis jiroveci pneumonia in human immunodeficiency virus (HIV)-negative immunocompromised patients is associated with high mortality rates. Although trimethoprim-sulfamethoxazole provides a very effective prophylaxis, pneumocystosis still occurs and may even be emerging due to suboptimal characterization of patients most at risk, hence precluding targeted prophylaxis.

METHODS

We retrospectively analyzed all cases of documented pneumocystosis in HIV-negative patients admitted in our institution, a referral center in the area, from January 1990 to June 2010, and extracted data on their underlying condition(s). To estimate incidence rates within each condition, we estimated the number of patients followed-up in our area for each condition by measuring the number of patients admitted with the corresponding international classification diagnostic code, through the national hospital discharge database (Program of Medicalization of the Information System [PMSI]).

RESULTS

From 1990 to 2010, 293 cases of pneumocystosis were documented, of which 154 (52.6%) tested negative for HIV. The main underlying conditions were hematological malignancies (32.5%), solid tumors (18.2%), inflammatory diseases (14.9%), solid organ transplant (12.3%), and vasculitis (9.7%). Estimated incidence rates could be ranked in 3 categories: 1) high risk (incidence rates >45 cases per 100,000 patient-year): polyarteritis nodosa, granulomatosis with polyangiitis, polymyositis/dermatopolymyositis, acute leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphoma; 2) intermediate risk (25-45 cases per 100,000 patient-year): Waldenström macroglobulinemia, multiple myeloma, and central nervous system cancer; and 3) low risk (<25 cases per 100,000 patient-year): other solid tumors, inflammatory diseases, and Hodgkin lymphoma.

CONCLUSIONS

These estimates may be used as a guide to better target pneumocystosis prophylaxis in the groups most at risk.

Pathological and protective immunity to Pneumocystis infection

Pneumocystis jirovecii is a common opportunistic infection in the HIV-positive population and is re-emerging as a growing clinical concern in the HIV-negative immunosuppressed population. Newer targeted immunosuppressive therapies and the discovery of rare genetic mutations have furthered our understanding of the immunity required to clear Pneumocystis infection. The immune system can also mount a pathologic response against Pneumocystis following removal of immunosuppression and result in severe damage to the host lung. The current review will examine the most recent epidemiologic studies about the incidence of Pneumocystis in the HIV-positive and HIV-negative populations in the developing and developed world and will detail methods of diagnosis for Pneumocystis pneumonia. Finally, this review aims to summarize the known mediators of immunity to Pneumocystis and detail the pathologic immune response leading to Pneumocystis-related immune reconstitution inflammatory syndrome.

Single-day trimethoprim/sulfamethoxazole prophylaxis for Pneumocystis pneumonia in children with cancer

OBJECTIVE

To determine whether a simplified, 1-day/week regimen of trimethoprim/sulfamethoxazole is sufficient to prevent Pneumocystis (jirovecii [carinii]) pneumonia (PCP). Current recommended regimens for prophylaxis against PCP range from daily administration to 3 consecutive days per week dosing.

STUDY DESIGN

A prospective survey of the regimens adopted for the PCP prophylaxis in all patients treated for childhood cancer at pediatric hematology-oncology centers of the Associazione Italiana Ematologia Oncologia Pediatrica.

RESULTS

The 20 centers participating in the study reported a total of 2466 patients, including 1093 with solid tumor and 1373 with leukemia/lymphoma (or primary immunodeficiency; n = 2). Of these patients, 1371 (55.6%) received the 3-day/week prophylaxis regimen, 406 (16.5%) received the 2-day/week regimen, and 689 (27.9%), including 439 with leukemia/lymphoma, received the 1-day/week regimen. Overall, only 2 cases of PCP (0.08%) were reported, both in the 2-day/week group. By intention to treat, the cumulative incidence of PCP at 3 years was 0.09% overall (95% CI, 0.00-0.40%) and 0.51% for the 2-day/week group (95% CI, 0.10%-2.00%). Remarkably, both patients who failed had withdrawn from prophylaxis.

CONCLUSION

A single-day course of prophylaxis with trimethoprim/sulfamethoxazole may be sufficient to prevent PCP in children with cancer undergoing intensive chemotherapy regimens. This simplified strategy might have implications for the emerging need for PCP prophylaxis in other patients subjected to the increased use of biological and nonbiological agents that induce higher levels of immune suppression, such as those with rheumatic diseases.

Increasing Pneumocystis pneumonia, England, UK, 2000-2010

After an increase in the number of reported cases of Pneumocystis jirovecii pneumonia in England, we investigated data from 2000-2010 to verify the increase. We analyzed national databases for microbiological and clinical diagnoses of P. jirovecii pneumonia and associated deaths. We found that laboratory-confirmed cases in England had increased an average of 7% per year and that death certifications and hospital admissions also increased. Hospital admissions indicated increased P. jirovecii pneumonia diagnoses among patients not infected with HIV, particularly among those who had received a transplant or had a hematologic malignancy. A new risk was identified: preexisting lung disease. Infection rates among HIV-positive adults decreased. The results confirm that diagnoses of potentially preventable P. jirovecii pneumonia among persons outside the known risk group of persons with HIV infection have increased. This finding warrants further characterization of risk groups and a review of P. jirovecii pneumonia prevention strategies.

Fever in Common Infectious Diseases

#x203A; Infection of the respiratory tract is the most common reason for seeking medical advice and hospital admission in children. A viral upper respiratory tract infection (URTI) is the most common infection of the respiratory tract.

› In developing countries, acute respiratory infection remains a leading cause of childhood mortality, causing an estimated 1.5–2 million deaths annually in children younger than 5 years of age.

› In developed countries, viruses are responsible for most upper and lower respiratory tract infections, including pharyngitis and pneumonia.

› Although the degree of fever cannot differentiate between viral and bacterial diseases, high fever is associated with a greater incidence of serious bacterial diseases such as pneumonia or meningitis.

› Worldwide, diarrheal disease is the leading cause of childhood deaths under 5 years of age.

› If the fever does not have an evident source, urinary tract infection (UTI) should be considered, particularly if the fever is greater than 39.0°C and persists for longer than 24–48 h.

› Widespread vaccinations against bacteria causing meningitis, such as Hib, and vaccines against meningococci and pneumococci have dramatically reduced the incidence of meningitis.

› A child with fever and nonblanching rash should be promptly evaluated to exclude meningococcal diseases.

› Young children with malaria may present with irregular fever and not with typical paroxysms of fever, occurring particularly in early falciparum infection or as a consequence of previous chemoprophylaxis, which modifies the typical pattern of fever.

Successful intermittent prophylaxis with trimethoprim/sulfamethoxazole 2 days per week for Pneumocystis carinii (jiroveci) pneumonia in pediatric oncology patients

OBJECTIVE

This study was conducted to determine the efficacy of dosing trimethoprim/sulfamethoxazole on 2 consecutive days per week for the prevention of Pneumocystis carinii (jiroveci) pneumonia in a pediatric leukemia and lymphoma population and to determine whether trimethoprim/sulfamethoxazole contributes to neutropenia during maintenance therapy.

METHODS

Charts were reviewed for all pediatric patients with leukemia and lymphoma diagnosed between January 1, 1993, and December 31, 2002. Data were collected through April 1, 2004.

RESULTS

A total of 575 charts were reviewed; 529 patients were included in the analysis. A total of 482 (345 leukemia, 137 lymphoma) patients were evaluated on trimethoprim/sulfamethoxazole dosed 2 consecutive days per week for 268074 patient-days. No breakthrough cases were documented in compliant patients; 2 noncompliant patients developed P. carinii pneumonia. A total of 238 patients who were on trimethoprim/sulfamethoxazole prophylaxis and 13 patients who were receiving an alternative medication prophylaxis were evaluated for neutropenia during maintenance therapy. The median number of maintenance days on trimethoprim/sulfamethoxazole was 605.5 days and on alternative drug was 617 days. The median number of neutropenic maintenance days on trimethoprim/sulfamethoxazole was 15.5 days and on the alternative drug was 16 days. The median proportion of neutropenic days per patient was 0.029 on trimethoprim/sulfamethoxazole and 0.022 on the alternative drug.

CONCLUSIONS

Intermittent dosing of trimethoprim/sulfamethoxazole on 2 consecutive days per week is an effective alternative prophylactic regimen for P. carinii pneumonia in pediatric patients with leukemia and lymphoma. This analysis does not support a difference in neutropenia during maintenance therapy between patients who are treated with trimethoprim/sulfamethoxazole versus an alternative drug.

Prophylaxis of Pneumocystis carinii pneumonia with atovaquone in children with leukemia

BACKGROUND

Despite extensive studies of atovaquone in human immunodeficiency virus (HIV)-infected patients, there is little information about its efficacy as a prophylactic agent for Pneumocystis carinii pneumonia (PCP) in pediatric patients with cancer. Therefore, a retrospective analysis was conducted to determine the incidence of PCP in pediatric patients who received prophylactic atovaquone during treatment for acute leukemia.

METHODS

We reviewed the medical records of all patients treated at our institution for acute lymphoblastic leukemia or acute myeloid leukemia between 1994 and 2004. Only patients who were intolerant of trimethoprim-sulfamethoxazole (TMP-SMZ) and received atovaquone prophylaxis were included in the analysis.

RESULTS

Eighty-six patients were unable to tolerate TMP-SMZ and received daily atovaquone for PCP prophylaxis. PCP was not diagnosed in any patient who received atovaquone prophylaxis: the upper limit of the 95% confidence interval (CI) was 1.74 per 100 person-years.

CONCLUSIONS

Atovaquone is an efficacious alternative for PCP prophylaxis in pediatric patients who have leukemia and are intolerant of TMP-SMZ.

Clinical presentation and treatment outcome of sleeping sickness in Sudanese pre-school children

BACKGROUND

Existing data on human African trypanosomiasis (HAT) due to Trypanosoma brucei gambiense among children are limited. Here, we described the demographic, clinical, diagnostic, treatment and outcome characteristics of HAT in pre-school children from Kajo-Keji County, South Sudan in comparison with older patients.

METHODS

We did a retrospective analysis of HAT patients treated at the Kiri Sleeping Sickness Treatment Centre (SSTC), Kajo-Keji County, from June 2000 to December 2002.

RESULTS

Of 1958 HAT patients, 119 (6.1%) were pre-school children (<6 years) including 56 (47%) in first-stage illness and 63 (53%) in second-stage. The proportion of children in second-stage HAT was significantly higher in very young children (<2 years). Walking and speech disturbances were more frequent in second-stage HAT but other neurological symptoms and signs were not associated with disease stage. Pentamidine treatment for first-stage illness was very safe and effective among pre-school children. In contrast, 4.9% of pre-school children in second-stage illness died during melarsoprol treatment and 46% had > or = 1 severe adverse event(s). Macular rash, jaundice and skin necrosis on injection site were significantly more frequent in this age group (p<0.05). Melarsoprol-induced encephalopatic syndrome was less frequent but more severe than in older age groups.

CONCLUSION

The clinical features of T. b. gambiense HAT among pre-school children are insufficiently stage-specific. Therefore, laboratory-based staging is mandatory to prevent unnecessary harm to HAT patients caused by the high toxicity of melarsoprol.

Prevention of infection due to Pneumocystis spp. in human immunodeficiency virus-negative immunocompromised patients

Pneumocystis infection in humans was originally described in 1942. The organism was initially thought to be a protozoan, but more recent data suggest that it is more closely related to the fungi. Patients with cellular immune deficiencies are at risk for the development of symptomatic Pneumocystis infection. Populations at risk also include patients with hematologic and nonhematologic malignancies, hematopoietic stem cell transplant recipients, solid-organ recipients, and patients receiving immunosuppressive therapies for connective tissue disorders and vasculitides. Trimethoprim-sulfamethoxazole is the agent of choice for prophylaxis against Pneumocystis unless a clear contraindication is identified. Other options include pentamidine, dapsone, dapsone-pyrimethamine, and atovaquone. The risk for PCP varies based on individual immune defects, regional differences, and immunosuppressive regimens. Prophylactic strategies must be linked to an ongoing assessment of the patient's risk for disease.

Opportunistic infections in patients with and patients without Acquired Immunodeficiency Syndrome

In the next decade, longer survival of patients with cancer and more-aggressive therapies applied to common conditions, such as asthma and rheumatoid arthritis, will result in a larger population with significant immune system defects. Many in this population will be at risk for opportunistic infections, which are familiar to doctors who have treated people infected with human immunodeficiency virus (HIV). However, the epidemiology, presentation, and outcome of these infections in patients with an immune system defect, other than that caused by HIV infection, may be different than those encountered in patients with acquired immunodeficiency syndrome. Reviewed are 4 common opportunistic infections: Pneumocystis carinii pneumonia, cryptococcosis, atypical mycobacterial infection, and cytomegalovirus infection. Emphasized are the important differences among these groups at risk.

Pneumocystis carinii pneumonia in a human immunodeficiency virus-uninfected patient with sickle cell crisis

Pneumocystis carinii pneumonia (PCP) usually occurs in the setting of preexisting immunosuppression. We present a case of PCP that occurred in an HIV-negative woman with severe sickle cell disease.

Peripheral blood CD4 + T-lymphocyte counts during Pneumocystis carinii pneumonia in immunocompromised patients without HIV infection

STUDY OBJECTIVES

To assess the potential use of peripheral blood CD4 + T-lymphocyte counts (CD4 + counts) as a clinically useful biological marker to identify specific immunocompromised patients (without HIV infection) at high risk for Pneumocystis carinii pneumonia (PCP).

DESIGN

Prospective observational study.

SETTING

Three hundred seventy-five-bed tertiary-care urban referral teaching hospital, and 250-bed community-based referral hospital.

PATIENTS

One hundred seventy-one consecutive confirmed HIV-seronegative hospitalized and ambulatory adults, including 22 patients with active PCP, 8 patients with bacterial pneumonia, 24 persons in two groups considered at high clinical risk, 38 persons in two groups considered at low or undefined risk, and 79 persons in four groups considered not at risk for PCP (including healthy individuals).

MEASUREMENTS AND RESULTS

Compared to counts in healthy individuals, median CD4 + counts were significantly decreased in patients with active PCP (61 cells/microL vs 832 cells/microL; p = 0.001) where 91% of patients had a CD4 + count < 300 cells/microL at the time of PCP diagnosis. Median CD4 + counts were also reduced in the high clinical risk groups of recent organ transplant recipients (117 cells/microL; p = 0.007), 64% with < 300 cells/microL, and patients receiving chemotherapy (221 cells/microL; p<0.01), 80% with < 300 cells/microL. For the low or undefined clinical risk groups, the median CD4 + counts were not significantly reduced, although 39 to 46% of individuals receiving long-term corticosteroid therapy (alone or in combination with other agents) had CD4 + counts < 300 cells/microL. Median CD4 + counts in individuals considered not at risk for PCP were similar to those in healthy subjects. Compared to counts in patients with active PCP, median CD4 + counts were significantly higher in bacterial pneumonia patients (486 cells/microL; p<0.05), but similar to those in healthy subjects.

CONCLUSIONS

These data suggest that for immunosuppressed persons without HIV infection (especially in low or undefined PCP risk groups), CD4 + counts may be a useful clinical marker to identify specific individuals at particularly high clinical risk for PCP and may help to guide chemoprophylaxis.

Pneumocystis carinii pneumonia: pitfalls of prophylaxis

Pneumocystis carinii pneumonia (PCP) occurs commonly in immunocompromised patients. Sulfamethoxazole-trimethoprim (SMX-TMP) is effective prophylaxis, although PCP may still occur despite apparently adequate use. We report three cases of PCP which highlight some of the pitfalls of prophylaxis.

Therapeutic progress. IV: Treatment and prophylaxis of Pneumocystis carinii infection

Co-trimoxazole presently remains the first choice for prophylaxis and treatment of Pneumocystis carinii infections. The high incidence of adverse reactions experienced by patients taking co-trimoxazole has led to a number of trials comparing it with other antipneumocystis agents. Adjuvant therapy with corticosteroids may benefit patients with severe P. carinii pneumonia. This paper reviews the standard treatments for P. carinii pneumonia, some of the newer agents such as atovaquone, recently licensed in the U.K., and a variety of novel agents being assessed for treatment and prophylaxis. Current recommendations may change over the new few years.

An outbreak of Pneumocystis carinii pneumonia in children with malignancy

An outbreak of Pneumocystis carinii pneumonia (PCP) in three patients within a 6 week period was reported. Two patients had acute lymphoblastic leukaemia and one had brain-stem glioma. They shared common features of immunosuppression and absence of cotrimoxazole prophylaxis and had been nursed in the same room. The severity of PCP and its response to treatment may be related to the degree of immunosuppression. Because of the morbidity and mortality of PCP, chemoprophylaxis should be given to all at-risk cases. Furthermore, isolation of patients with PCP should be considered in view of increasing evidence of nosocomial transmission.

Pneumocystis carinii pneumonia in cancer patients

Concern has been arisen about the recently reported increasing incidence of PCP in patients with cancer and the potential transmissibility of this infection. Whether or not there is an increase in the incidence of P. carinii infections, PCP should be considered in the differential diagnosis of pulmonary infiltrates in bone marrow transplant recipients, in patients with hematologic neoplasms and in patients with primary or metastatic brain neoplasms. Intensity of immunosuppression plays a crucial role, especially long-term (> 2 months) corticosteroid treatment. PCP is usually manifested clinically during augmentation or during tapering of corticosteroid dose. Thus, if the chest radiograph of a high-risk patient shows diffuse infiltrates, bronchoscopy and bronchoalveolar lavage should be done immediately. Treatment options are the same as for the AIDS population, except that TMP-SMX is tolerated better in non-AIDS patients. The role of supportive care, including mechanical ventilation in such patients should not be underestimated. Oral therapy with dapsone-trimethoprim or with atovaquone, can be as effective as conventional therapy in mild disease, permitting treatment on an outpatient basis. PCP is often preventable and our understanding has improved about when prophylaxis should be initiated. In the future, the emergence of new technologies for diagnosis and of new agents for treatment and prophylaxis, will bring us closer to the goal of controlling this serious infection.

Single and combined humoral and cell-mediated immunotherapy of Pneumocystis carinii pneumonia in immunodeficient scid mice

Homozygous mutant scid/scid (severe combined immunodeficiency) mice (referred to as scid mice) lack both specific humoral and cell-mediated immune functions and are exemplary in vivo models for analysis of host-parasite relationships. In our colony, scid mice routinely and predictably develop spontaneous Pneumocystis carinii pneumonia (PCP) with high morbidity. Previous studies have identified both T cells (specifically, CD4+ cells) and antibody as independent mechanisms of effective anti-P. carinii resistance; however, CD4+ T cells also cause an often fatal hyperinflammatory reaction. The current study has explored the optimal application of these immune components for conferring protection against P. carinii. Anti-P. carinii hyperimmune serum was highly effective at reducing the number of P. carinii organisms in early, intermediate, and advanced stages of PCP and was capable of increasing the mean life expectancy of P. carinii-infected scid mice by more than threefold if provided on a continuing basis. When a short course of hyperimmune-serum therapy was provided prior to transfer of P. carinii-sensitized normal lymphocytes, scid mice were rendered permanently free of P. carinii without the pathological sequelae of the hyperinflammatory reaction. These findings are discussed in the contexts of mechanism and clinical relevance.

Pneumocystis carinii infections in HIV-infected children

Since 1981, 1200 children with acquired immunodeficiency syndrome have been reported to the Centers for Disease Control. Among these children, Pneumocystis carinii has been the leading cause of serious morbidity and mortality. This review discusses the epidemiology, diagnosis, and treatment of P. carinii.

Rapid detection of Pneumocystis carinii in bronchoalveolar lavage samples by using Cellufluor staining

Cellufluor (Calcofluor white) has been found to be a useful, rapid chemofluorescent stain for detection of Pneumocystis carinii cysts in bronchoalveolar lavage samples. When compared with toluidine blue O and Giemsa stains on 45 specimens (22 positive and 23 negative), the sensitivity and specificity of the Cellufluor stain were 95 and 100%, respectively.

Diffuse interstitial pneumonitis after pulmonary irradiation for metastatic Wilms' tumor. A report from the National Wilms' Tumor Study

To evaluate the frequency, etiology, and outcome of diffuse interstitial pneumonitis after treatment of children with Stage IV (favorable histologic type) Wilms' tumor using whole-lung and abdominal radiation therapy, and combination chemotherapy, all cases reported in such patients entered on National Wilms' Tumor Study 3 were reviewed. Diffuse interstitial pneumonitis was reported in 13.0% of patients. The etiology was varicella, one patient; Pneumocystis carinii, three patients; and unknown, 15 patients. The time elapsed after the completion of whole-lung irradiation did not distinguish those patients with pneumonitis due to P. carinii from those with pneumonitis of unknown etiology. All three children with pneumonitis due to P. carinii survived the episode, whereas only four of 15 (27%) patients with pneumonitis of unknown etiology survived the episode. Management of Wilms' tumor patients who develop diffuse interstitial pneumonitis after whole-lung irradiation should include a diagnostic procedure known to be sensitive for the diagnosis of P. carinii infection.

Disseminated infection of Pneumocystis carinii in a patient with the acquired immunodeficiency syndrome

This report describes the histopathology of a disseminated Pneumocystis carinii infection in a 24-year-old Japanese male haemophiliac diagnosed as having the acquired immunodeficiency syndrome. He developed respiratory symptoms, and Pneumocystis carinii pneumonia was confirmed by transbronchial lung biopsy. On the 70th day of hospitalization the patient died. Autopsy findings revealed Pneumocystis carinii not only in the lungs but also in the stomach, jejunum, ileum, colon, mesoappendix, abdominal lymph nodes, diaphragm, and thyroid gland.

Treatment and prophylaxis for Pneumocystis carinii pneumonia

Without treatment, Pneumocystis carinii pneumonitis is almost always fatal in the immunocompromised host. Here, Walter Hughes discusses proven and potential treatments, and methods of chemoprophylaxis in high-risk patients. Two drugs, pentamidine isethionate and trimethoprimsulfamethoxazole, are equally effective therapeutically - permitting the recovery of approximately 75% of patients - but the latter drug combination is preferred because of its lower toxicity and fewer adverse effects. The pneumonitis can be prevented by prophylactic administration of trimethoprim-sulfamethoxazole. Other drugs with proven efficacy or under study include Fansidar, dapsone, trimetrexate and difluoromethylornithine.

Effect of trimethoprim/sulfamethoxazole prophylaxis on outcome of childhood lymphocytic leukemia. A Pediatric Oncology Group Study

The Pediatric Oncology Group (POG) undertook a prospective randomized trial using a single chemotherapy regimen with or without trimethoprim/sulfamethoxazole (TS). In a previous acute lymphocytic leukemia (ALL) study of initial therapy, investigators were free to use TS prophylaxis or not. Analysis of those data seemed to favor TS for duration of continuous complete remission. In the study reported here, of 126 randomized patients with ALL, 63 received TS. There was no effect of TS on disease-free survival after 3 years follow-up. Overall severe toxicity did not differ. However, granulocytopenia was somewhat more severe in the TS group. Hepatic toxicity, measured by enzyme elevation approached significance in the TS group versus controls. Some institutions declined randomization and treated with or without TS as a routine. Outcome and toxicities did not differ from randomized patients. There was no statistically significant effect on severe, life-threatening or fatal infection between the randomized TS versus control groups. Children not receiving TS developed varicella more often, a disease for which one would not expect TS to show a preventative effect. Pneumocystis pneumonias were not reported. The authors conclude that TS prophylaxis did not increase the continuous complete remission rate in children with ALL or decrease the incidence of infection. Toxicity is somewhat higher on TS.

AIDS and parasitic infections, including Pneumocystis carinii and cryptosporidiosis

AIDS is a disorder that the pediatrician must consider when evaluating children with a variety of clinical conditions, including overwhelming infection with a number of parasites. This article discusses these opportunistic parasitic infections, focusing on their link with AIDS.