Pneumocystis carinii pneumonia and methotrexate therapy

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.

Lymphopenia associated with adjuvant anthracycline/ taxane regimens

BACKGROUND

We observed 2 cases of Pneumocystis carinii pneumonia (PCP) occurring in HIV-negative patients during treatment with dose-dense chemotherapy with doxorubicin/cyclophosphamide (AC) followed by paclitaxel (T). These represent the first case reports of PCP occurring during dose-dense chemotherapy for breast cancer. Because lymphocyte depletion is thought to predispose patients to PCP, we explored whether the shortened intervals between cycles during dose-dense chemotherapy might place patients at risk for lymphocyte depletion and thereby a potentially increased risk of opportunistic infection.

PATIENTS AND METHODS

Three cohorts of patients were analyzed. Cohort 1 involved 135 patients receiving dose-dense AC --> T on a phase II study. Cohort 2 included 64 patients who received treatment with dose-dense AC --> albumin-bound paclitaxel on a phase II clinical trial. Cohort 3 consisted of 59 patients who received AC --> T given every 3 weeks who were identified from the Clinical Research Information System database at Dana-Farber Cancer Institute. For cohorts 1 and 3, the electronic medical record was reviewed to determine absolute lymphocyte counts (ALCs) and absolute neutrophil counts (ANCs) for day 1 of each of the 8 cycles of treatment. For cohort 2, data was prospectively collected and entered into an electronic database. The lowest ALC obtained by each patient on day 1 of any cycle was termed the nadir.

RESULTS

Patients experienced grade 3 (ALC < 500 cells/mm3) or grade 4 (ALC < 200 cells/mm3) lymphopenia in all 3 cohorts: 63% with dose-dense AC -->T, 23.4% in dosedense AC --> albumin-bound paclitaxel, and 69% with dose-dense AC --> T every 3 weeks. Patients experienced their lowest median ALC count at cycle 5 of treatment in all 3 cohorts, with a median nadir of 400 cells/mm3 in cohort 1, 690 cells/mm3 in cohort 2, and 400 cells/mm3 in cohort 3.

CONCLUSION

The majority of patients receiving AC --> T every 2 or 3 weeks experience grade 3/4 lymphopenia. Median lymphocyte counts appear to be lowest around cycle 5, the point at which we observed 2 cases of PCP. Lymphocyte counts appear to be reaching a low enough level to place patients at risk for opportunistic infection during treatment with dosedense AC --> T and with AC --> T given every 3 weeks.

Evaluation of Pneumocystis pneumonia infection risk factors in patients with connective tissue disease

We conducted a retrospective, clinical evaluation of connective tissue disease (CTD) patients who were tested for either sputum or bronchoalveolar lavage fluid Pneumocystis polymerase chain reaction (PC-PCR) and analyzed the risk factors that cause Pneumocystis pneumonia (PCP) susceptibility and fatality. PC-PCR was performed on 66 CTD patients who presented with symptoms, data, or radiological findings strongly suggesting respiratory infection. Patients with higher oral corticosteroid doses, use of oral methotrexate (MTX), bilateral lung findings, positive beta-D-glucan, and no prophylaxis use were more susceptible to PCP. They had significantly low immunoglobulin G and significantly high beta-D-glucan and lactate dehydrogenase. Survivors and nonsurvivors of PCP were also evaluated. Poor prognoses were observed with older age, elevated beta-D-glucan, rheumatoid arthritis (RA) patients using MTX, hypoxemia, bilateral lung findings, and mechanical ventilation use. Nonsurvivors had significantly lower lymphocytes, oxygen saturation, and significantly higher beta-D-glucan. In RA, poor prognoses were seen with those taking MTX. Disease duration, underlying pulmonary complications, and oral corticosteroid doses did not lead to poor prognoses in RA. Because PCP in CTD leads to abrupt onset of symptoms with poor survival rates, early diagnosis and initiation of treatment are critical, and it is essential for clinicians to recognize risk factors that predispose patients to PCP and its mortality.

An analysis of the utilisation of chemoprophylaxis against Pneumocystis jirovecii pneumonia in patients with malignancy receiving corticosteroid therapy at a cancer hospital

Pneumocystis jirovecii pneumonia (PCP) is associated with high mortality in immunocompromised patients without human immunodeficiency virus infection. However, chemoprophylaxis is highly effective. In patients with solid tumours or haematologic malignancy, several risk factors for developing PCP have been identified, predominantly corticosteroid therapy. The aims of this study were to identify the potentially preventable cases of PCP in patients receiving corticosteroid therapy at a tertiary care cancer centre and to estimate the frequency of utilisation of chemoprophylaxis in these patients. Two retrospective reviews were performed. Over a 10-year period, 14 cases of PCP were identified: no cases were attributable to failed chemoprophylaxis, drug allergy or intolerance. During a 6-month period, 73 patients received high-dose corticosteroid therapy (⩾25 mg prednisolone or ⩾4 mg dexamethasone daily) for ⩾4 weeks. Of these, 22 (30%) had haematologic malignancy, and 51 (70%) had solid tumours. Fewer patients with solid tumours received prophylaxis compared to patients with haematologic malignancy (3.9 vs 63.6%, P<0.0001). Guidelines for PCP chemoprophylaxis in patients with haematologic malignancy or solid tumours who receive corticosteroid therapy are proposed. Successful primary prevention of PCP in this population will require a multifaceted approach targeting the suboptimal prescribing patterns for chemoprophylaxis.

Fungal infections in immunocompromised individuals

This article examines the expression of fungal infections seen with different immunodeficiency states and discusses how the sequential appearance of different diseases serves as a harbinger of clinical disease progression. The effect of an immunocompromised state on the medical history, physical findings, and natural history of fungal infections are discussed. The appearance and increased frequency of rare fungal infections, made possible by immunosuppression, are highlighted.

Drug-induced pulmonary disease

Drug-induced disease of any system or organ can be associated with high morbidity and mortality, and it is tremendously costly to the health care of our country. More than 100 medications are known to affect the lungs adversely, including the airways in the form of cough and asthma, the interstitium with interstitial pneumonitis and noncardiac pulmonary edema, and the pleura with pleural effusions. Patients commonly do not even know what medications they are taking, do not bring them to the physician's office for identification, and usually do not relate over-the-counter medications with any problems they have. They assume that all nonprescription drugs are safe. Patients also believe that if they are taking prescription medications at their discretion, meaning on an as-needed basis, then these medications are also not important. This situation stresses just how imperative it is for the physician to take an accurate drug history in all patients seen with unexplained medical situations. Cardiovascular drugs that most commonly produce a pulmonary abnormality are amiodarone, the angiotensin-converting enzyme inhibitors, and beta-blockers. Pulmonary complications will develop in 6% of patients taking amiodarone and 15% taking angiotensin-converting enzyme inhibitors, with the former associated with interstitial pneumonitis that can be fatal and the latter associated with an irritating cough that is not associated with any pathologic or physiologic sequelae of consequence. The beta-blockers can aggravate obstructive lung disease in any patient taking them. Of the antiinflammatory agents, acetylsalicyclic acid can produce several different airway and parenchymal complications, including aggrevation of asthma in up to 5% of patients with asthma, a noncardiac pulmonary edema when levels exceed 40 mg/dl, and a pseudosepsis syndrome. More than 200 products contain aspirin. Low-dose methotrexate is proving to be a problem because granulomatous interstitial pneumonitis develops in 5% of those patients receiving it. This condition occurs most often in patients receiving the drug for rheumatoid arthritis, but it has been reported in a few patients receiving it for refractory asthma. Chemotherapeutic drug-induced lung disease is almost always associated with fever, thus mimicking opportunistic infection, which is the most common cause of pulmonary complications in the immunocompromised host. However, in 10% to 15% of patients, the pulmonary infiltrate is due to an adverse effect from a chemotherapeutic agent. This complication is frequently fatal even when recognized early.(ABSTRACT TRUNCATED AT 400 WORDS)