Facteurs favorisants de la pneumocystose (PPC) chez les malades immunodéprimés non infectés par le VIH

The role of CD4 cell count as discriminatory measure to guide chemoprophylaxis against Pneumocystis jirovecii pneumonia in human immunodeficiency virus-negative immunocompromised patients: A systematic review

BACKGROUND

In recent years, the incidence of Pneumocystis jirovecii pneumonia (PJP) has increased in immunocompromised patients without human immunodeficiency virus (HIV) infection. Chemoprophylaxis with trimethoprim-sulfamethoxazole (TMP-SMX) is highly effective in preventing PJP in both HIV-positive and -seronegative patients. In HIV-positive patients, the risk of PJP is strongly correlated with decreased CD4 cell count. The role of CD4 cell count in the pathogenesis of PJP in non-HIV immunocompromised patients is less well studied. For most immunosuppressive conditions, no clear guidelines indicate whether to start TMP-SMX.

METHOD

We conducted a systematic literature review with the aim to provide a comprehensive overview on the role of CD4 cell counts in managing the risk of PJP in HIV-seronegative patients.

RESULTS

Of the 63 individual studies retrieved, 14 studies report on CD4 cell counts in a variety of immunosuppressive conditions. CD4 cell count were <200/μL in 73.1% of the patients.

CONCLUSION

CD4 cell count <200/μL is a sensitive biomarker to identify non-HIV immunocompromised patients who are at risk for PJP. Measuring CD4 cell counts could help clinicians identify patients who may benefit from TMP-SMX prophylaxis.

Do inhaled corticosteroids increase the risk of Pneumocystis pneumonia in people with lung cancer?

Pneumocystis pneumonia (PCP) is a life-threatening infection in immunocompromised patients. It is relatively uncommon in patients with lung cancer. We report a case of PCP in a 59-year-old man with a past medical history of chronic obstructive pulmonary disease treated with formoterol and a moderate daily dose of inhaled budesonide. He had also advanced stage non-small lung cancer treated with concurrent chemo-radiation with a cisplatin-etoposide containing regimen. The diagnosis of PCP was suspected based on the context of rapidly increasing dyspnea, lymphopenia and the imaging findings. Polymerase chain reaction testing on an induced sputum specimen was positive for Pneumocystis jirovecii. The patient was treated with oral trimethoprim-sulfamethoxazole and systemic corticotherapy and had showed clinical and radiological improvement. Six months after the PCP diagnosis, he developed a malignant pleural effusion and expired on hospice care. Through this case, we remind the importance of screening for PCP in lung cancer patients under chemotherapeutic regimens and with increasing dyspnea. In addition, we alert to the fact that long-term inhaled corticosteroids may be a risk factor for PCP in patients with lung cancer. Despite intensive treatment, the mortality of PCP remains high, hence the importance of chemoprophylaxis should be considered.

Possible pandemic HIN1 influenza complicated by Pneumocystis jirovecii pneumonia in an HIV-infected patient

Immune response to a pandemic influenza A 2009 (H1N1) virus infection can influence the way a second unrelated pathogen is handled by the host. We report here a case of pandemic flu with marked CD4 T-cell lymphopenia complicated by a possible Pneumocystis jirovecii pneumonia in an HIV-infected patient.