Atypical distribution of Pneumocystis carinii infiltrates during radiation therapy

Apical Pneumocystis jiroveci as an AIDS defining illness: A case report illustrating a change in the paradigm

Pneumocystis jiroveci pneumonia is a common acquired immune deficiency syndrome defining illness. Pneumocystis jiroveci pneumonia is classically described as having symmetrical bilateral perihilar ground-glass opacities on chest radiographs. We present an "atypical" case of Pneumocystis jiroveci pneumonia presenting as symmetric biapical cystic spaces with relative sparing of the remainder of the lungs in a 22 year-old male, previously undiagnosed with acquired immune deficiency syndrome. Our case illustrates that formerly unusual presentations of Pneumocystis jiroveci pneumonia are becoming more common as acquired immune deficiency syndrome defining illnesses as more patients are being imaged with further imaging such as high resolution computed tomography.

Pneumocystis pneumonia in a patient with non-small cell lung cancer (NSCLC) treated with pemetrexed containing regimen

Pneumocystis pneumonia is typically life-threatening in immunocompromised patients. It is relatively uncommon in patients with lung cancer. We report a case of pneumocystis pneumonia in a patient with advanced stage non-small cell lung cancer (NSCLC) following treatment with concurrent chemoradiation with a pemetrexed containing regimen. To our knowledge, this is the first report on pneumocystis pneumonia following administration of pemetrexed containing regimen.

Diagnostic strategy in cancer patients with acute respiratory failure

OBJECTIVE

Nearly 15% of cancer patients experience acute respiratory failure (ARF) requiring admission to the intensive care unit, where their mortality is about 50%. This review focuses on ARF in cancer patients. The most recent literature is reviewed, and emphasis is placed on current controversies, most notably the risk/benefit ratio of fiberoptic bronchoscopy and BAL in patients with severe hypoxemia.

BACKGROUND

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is the cornerstone of the causal diagnosis. However, the low diagnostic yield of about 50%, related to the widespread use of broad-spectrum antimicrobial therapy in cancer patients, has generated interest in high-resolution computed tomography (HRCT) and primary surgical lung biopsy. In patients with hypoxemia, bronchoscopy and BAL may trigger a need for invasive mechanical ventilation, thus considerably decreasing the chances of survival.

DISCUSSION

The place for recently developed, effective, noninvasive diagnostic tools (tests on sputum, blood, urine, and nasopharyngeal aspirates) needs to be determined. The prognosis is not markedly influenced by cancer characteristics; it is determined chiefly by the cause of ARF, need for mechanical ventilation, and presence of other organ failures. Although noninvasive ventilation reduces the need for endotracheal intubation and diminishes mortality rate, its prolonged use in patients with severe disease may preclude optimal diagnostic and therapeutic management. The appropriateness of switching to endotracheal mechanical ventilation in patients who fail noninvasive ventilation warrants evaluation.

CONCLUSION

This review discusses risks and benefits from invasive and non invasive diagnostic and therapeutic strategies in critically ill cancer patients with acute respiratory failure. Avenues for research are also suggested in order to improve survival in these very high risk patients.

Opportunistic pneumonia

Patients with abnormalities in their immune defense mechanisms are frequently encountered in the practice of medicine. These patients have increased susceptibility to infections that often involve the lung. Many of these infections are caused by opportunistic organisms that typically do not produce disease in individuals with a normally functioning immune system. To complicate the evaluation of these patients, they frequently develop noninfectious lung disease, which can have a radiographic appearance that is similar to infection. The purpose of this article is to present an approach to the evaluation of chest radiographic abnormalities in the immunocompromised patient with suspected pneumonia. Clinical information that is pertinent in the evaluation of immunocompromised patients is discussed. The various chest radiographic patterns seen in both infectious and noninfectious diseases that occur in the immunocompromised patient are reviewed. Integration of clinical information and radiographic findings in the development of a list of differential diagnoses is stressed.

Pneumonia carcinomatosa from small cell undifferentiated carcinoma of the lung presenting as "reverse radiation pneumonitis"

We describe a patient with recurrent small cell undifferentiated lung carcinoma after chemotherapy and mediastinal radiation therapy who presented with peripheral pulmonary infiltrates on chest radiograph. At autopsy the patient was found to have carcinomatous pneumonia confined to the radiographically abnormal lung. The descriptive term "reverse radiation pneumonitis" is applied in view of the striking nonsegmental distribution of these pulmonary infiltrates, which occurred only outside the irradiated field. In this patient, radiation therapy successfully controlled disease in the treated lung parenchyma, thus accounting for this unusual radiologic and histologic picture. Pneumonia carcinomatosa, occurring after lung irradiation, can therefore be added to the differential diagnosis of radiographic peripheral pulmonary infiltrates.