Pulmonary pathology in AIDS: atypical Pneumocystis carinii infection and lymphoid interstitial pneumonia

Chest X-ray findings in HIV- infected Highly Active Antiretroviral Treatment (HAART)-naïve patients

INTRODUCTION

Patients with human immunodeficiency virus (HIV) infection frequently present with a wide spectrum of pulmonary and cardiac complications from the virus, opportunistic infections and neoplasms that may be associated with a high mortality rate. Diseases of the respiratory tract account for about half of deaths from AIDS, while cardiac diseases account for more than a quarter of deaths from AIDS. This study aimed at determining the prevalence of pulmonary and cardiac diseases using a chest radiograph in HAART-naïve HIV-infected patients.

METHODS

This study was conducted at Lagos State University Teaching Hospital (LASUTH) HIV clinic between September 2010 and August 2011 amongst all registered HAART-naïve HIV/AIDS patients. Patients had posterior-anterior chest radiographs done in full inspiration. Participants were asked and aided to fill the structured questionnaires to obtain demographic data.

RESULTS

Out of a total of one hundred and two recruited for the study, 54 ( 52.94%) had a normal chest radiograph, while 48 (47.06%) had abnormal chest radiograph .The abnormal findings included, 27.45% who had bronchopneumonia, 6.86% cardiomegaly, 5.88% pulmonary tuberculosis, 5.88% radiological features of congestive cardiac failure, and 0.98% bronchitis.

CONCLUSION

It appears that more than half of HAART-naïve HIV-infected patients have normal chest radiographs. Bronchopneumonia (27.5%) is the commonest pulmonary abnormality associated with HIV infection, while the prevalence of pulmonary tuberculosis is 5.88%.

Undiagnosed AIDS in patients with progressive dyspnoea: an occupational risk for healthcare workers in Croatia

Pulmonary diseases are well documented and diverse in many patients with HIV in clinical stages 3 and 4. It is not unusual that these patients, most of whom do not know that they are already HIV-infected, are first examined and hospitalised by respiratory medicine specialists. While HIV-infection is relatively simple to diagnose if accompanied by advanced clinical manifestations and is regularly checked in patients with increased risk, this is not the case in low-risk patients, particularly in countries with low-level HIV epidemic and therefore low index of suspicion. Regular examination involves a series of tests, often including bronchoscopy with transbronchal lung biopsy in order to identify an interstitial lung disease and/or progressive dyspnoea. It is not uncommon that patients provide false or incomplete information about their lifestyle, which can mislead the clinician. At this point, HIV-infection is usually not suspected and healthcare workers may not strictly be following the safety principles which are otherwise applied when HIV-infection is known or suspect, although universal precautions are routine practice. At this point, the risk of exposure is the highest and HIV-transmission to healthcare workers is the most likely to occur. The cases presented here indicate that patients with progressive dyspnoea, which is typical of interstitial lung diseases, should undergo HIV-testing as a part of good clinical practice, even in a country with low-level HIV epidemic.

Pneumocystis jiroveci Pneumonia

Pneumocystis pneumonia (PCP) is one of the most common pulmonary infections in persons with impaired cell-mediated immunity, and particularly those infected with human immunodeficiency virus (HIV).1–7 Pneumocystis was first described in the lungs of guinea pigs, during experiments on American trypanosomiasis by Carlos Chagas8 in 1909 and by Antonio Carinii9 in 1910. Both considered the cysts of Pneumocystis as part of the trypanosome’s life cycle. Shortly afterward the Delanoes10 found identical forms in the lungs of rats that had not been infected with trypanosomes and recognized the organism as a separate species. The name Pneumocystis carinii, was given to this organism as a generic name (Greek:pneumon, “lung”; kystis, “cyst”), honoring Carinii.11

Malignant and benign lymphoid lesions of the lung

Lymphoid lesions of the lung produce a complex of problems for the practicing pathologist. Although these lesions are eventually referred to hematopathologists, it is still the general surgical pathologist who first encounters them and confronts the problem of formulating an initial diagnosis. Over the last 20 years there has been a revolution in our knowledge of the classification and natural history of the pulmonary lesions, a plethora of information which warrants a thorough review. The purpose of this discussion is to report the clinical features and courses, pathologic features and, when known, etiologies or pathogenesis of the major "primary" pulmonary lymphoid lesions and present a brief approach to differential diagnosis. I will divide the lesions into malignant and benign, discussing each in turn.

Lymphocytic interstitial pneumonitis and nonspecific interstitial pneumonitis

Nonspecific interstitial pneumonitis (NIP) and lymphocytic interstitial pneumonitis (LIP), with or without lymphocytic alveolitis, are poorly understood pulmonary complications of HIV infection. These disorders probably represent a spectrum of lymphoproliferative processes that overlap, rather than distinct illnesses. The clinical presentation, radiographic findings, and physiologic abnormalities in NIP and LIP are not specific and therefore require a biopsy for definitive diagnosis. The clinical course of these illnesses is generally favorable, even without specific treatment.

Pneumocystis carinii

Improved understanding of Pneumocystis carinii, in particular the widespread use of chemoprophylaxis, has resulted in a declining incidence of infection in patients infected with HIV since the late 1980s. Despite these advances, P. carinii pneumonia continues to represent an important cause of pulmonary disease in HIV-seropositive individuals who do not receive chemoprophylaxis or when breakthrough episodes occur. This article reviews the history, biology, clinical manifestations, prognostic markers, therapy, and chemoprophylaxis of P. carinii pneumonia in HIV-seropositive patients.