Changing patterns of respiratory disease in HIV positive patients in a referral centre in the United Kingdom between 1986-7 and 1990-1

Evaluation of the status of tuberculosis as part of the clinical case definition of AIDS in India

AIM

To assess HIV associated tuberculosis in a high tuberculosis prevalence setting and its status in the clinical case definition of AIDS.

METHODS

All HIV patients attending the infectious disease clinic, Varanasi, India between January 2001 and December 2003 were included in the study. They were stratified into three distinct immunological categories depending on their CD4 levels in accordance to Centers for Disease Control (CDC) classification. Tuberculosis of different organs was defined as detailed below.

RESULTS

Tuberculosis was the commonest opportunistic disease, seen in 163 patients. Of these, 68 had exclusively pulmonary tuberculosis, 55 extrapulmonary disease, and 40 the disseminated form. Pulmonary and extrapulmonary tuberculosis had low positive predictive value (PPV) (51% and 42%) for CD4 levels of <200 when compared with the disseminated form (specificity 87% and PPV 75%). Among 86 patients with radiological evidence of tuberculosis, typical radiological features of post-primary tuberculosis were present in 60 cases (70%). Other features such as effusion (14 patients, 16%) and miliary shadows (12 patients, 14%) were comparatively rare.

CONCLUSION

Keeping pulmonary and extrapulmonary forms of tuberculosis in AIDS defining illness should be reconsidered. In a similar way tuberculosis in HIV patients from areas endemic with tuberculosis occurs in patients with a wide range of immune status and has a better prognosis than other AIDS defining illnesses. Therefore the inclusion of tuberculosis in clinical case definition of AIDS is not justified.

Changes in the Pattern of Respiratory Diseases Necessitating Hospitalization of HIV-infectedPatients Since the Advent of Highly Active Antiretroviral Therapy

The incidence rates of opportunistic diseases, hospital admission and death have fallen markedly since the advent of highly active antiretroviral therapy (HAART). We examined the impact of HAART on the pattern of HIV-related respiratory diseases necessitating hospitalization. We retrospectively compared the numbers and etiologies of respiratory diseases diagnosed in HIV-infected patients hospitalized in the chest department of a Paris university hospital during the three years preceding widespread prescription of HAART in France (era 1, starting in July 1993) and the first three years of widespread HAART prescription (era 2, starting in July 1996). Respectively, 207 and 119 HIV-infected patients were admitted for respiratory disease in era 1 and era 2. Only 31.1% of patients admitted during era 2 were receiving HAART. Pulmonary opportunistic infections other than Pneumocystis carinii pneumonia (PCP) (p = 0.0008) and exacerbations of chronic bronchial disease due to gram-negative bacilli (p = 0.04) virtually disappeared in era 2. In contrast, PCP, bacterial pneumonia, tuberculosis, pulmonary Kaposi's sarcoma and pulmonary non-Hodgkin lymphoma showed only a twofold decrease in era 2, while lung cancer was more frequent (p = 0.004). The frequency of severe respiratory diseases necessitating hospitalization of HIV-infected patients has fallen since the advent of HAART, and their etiologic distribution has changed.

Pleural effusions in patients with AIDS

OBJECTIVE

To describe the range of pathology causing pleural effusions in HIV infected patients with acute respiratory episodes and to attempt to identify whether any associated radiological abnormalities enabled aetiological discrimination.

METHODS

Prospective study of chest radiographs of 58 consecutive HIV infected patients with pleural effusion and their microbiological, cytological, and histopathological diagnoses.

RESULTS

A specific diagnosis was made in all cases. Diagnoses were Kaposi's sarcoma, 19 patients; para-pneumonic effusion, 16 patients; tuberculosis, eight patients; Pneumocystis carinii pneumonia, six patients; lymphoma, four patients; pulmonary embolus, two patients; and heart failure, aspergillus/leishmaniasis, and Cryptococcus neoformans, one case each. Most effusions (50/58) were small. Bilateral effusions were commoner in Kaposi's sarcoma (12/19) and lymphoma (3/4) than in para-pneumonic effusion (3/16). Concomitant interstitial parenchymal shadowing did not aid discrimination. A combination of bilateral effusions, focal air space consolidation, intrapulmonary nodules, and/or hilar lymphadenopathy suggests Kaposi's sarcoma. Unilateral effusion with focal air space consolidation suggests para-pneumonic effusion if intrapulmonary nodules are absent: if miliary nodules and/or mediastinal lymphadenopathy are detected, this suggests tuberculosis.

CONCLUSIONS

A wide variety of infectious and malignant conditions cause pleural effusions in HIV infected patients, the most common cause in this group was Kaposi's sarcoma. The presence of additional radiological abnormalities such as focal air space consolidation, intrapulmonary nodules, and mediastinal lymphadenopathy aids aetiological discrimination.

Pulmonary aspergillosis and invasive disease in AIDS: review of 342 cases

Aspergillosis is an infrequent but commonly fatal infection among HIV-infected individuals. We review 342 cases of pulmonary Aspergillus infection that have been reported among HIV-infected patients, with a focus on invasive disease. Invasive pulmonary aspergillosis usually occurs among patients with <50 CD4 cells/mm3. Major predisposing conditions include neutropenia and steroid treatment. Fever, cough, and dyspnea are each present in >60% of the cases. BAL is often suggestive, but biopsy specimens are necessary for definite diagnosis. Amphotericin B is the mainstay of treatment and mortality is > 80%. Avoiding neutropenia and judicious use of steroids may be helpful in prevention. Aggressive diagnostic approach, early initiation of treatment, adequate dosing of antifungals, and close follow-up may improve the currently dismal prognosis.

Pulmonary complications of HIV infection: autopsy findings

STUDY OBJECTIVES

To describe the pulmonary complications in patients with HIV infection, and the changes in the incidence of these complications over a 12-year period.

DESIGN

Retrospective review of autopsy records.

SETTING

Two university-affiliated medical centers.

PATIENTS

We studied autopsy findings from 233 patients with HIV infection who died between 1985 and 1996. Demographic data, risk factors for HIV infection, and the lengths of hospital stay were obtained. The histologic and microbiological findings of the respiratory system, and the extrapulmonary organ involvement by Kaposi's sarcoma (KS), Pneumocystis carinii, Mycobacterium tuberculosis, and Mycobacterium avium complex were reviewed.

RESULTS

Ninety-two percent of the patients were black and 75% were male. The two most common identified risk factors for HIV infection were homosexuality (34%) and injection drug use (27%). Bacterial pneumonia was the most frequent pulmonary complication (42%). The two most common causes of bacterial pneumonia were Pseudomonas aeruginosa and Staphylococcus aureus. P carinii pneumonia (PCP) was found in 24%, with extrapulmonary involvement in 13%. Pulmonary mycobacterial infections were seen in 33%, with multiple extrapulmonary involvement. The most common site affected by KS was the lung. Of all pulmonary complications, only the incidence of PCP decreased over the 12-year period.

CONCLUSIONS

Recognizing the high incidence rate of bacterial pneumonia, the high frequency of pulmonary KS and the not uncommon occurrence of extrapulmonary P carinii infection in patients with HIV helps in improving their care.

CT manifestations of human immunodeficiency virus (HIV)-related pulmonary infections

The infectious pulmonary complications of acquired immunodeficiency syndrome (AIDS) are reviewed, with emphasis on the spectrum of CT imaging findings and diagnostic accuracy and limitations as reported in the current literature. Changes in epidemiologic trends for common AIDS-related infections and the associated ranges of CD4 lymphocyte counts, when these infections are typically encountered, are discussed.

Simplified sample processing combined with a sensitive one-tube nested PCR assay for detection of Pneumocystis carinii in respiratory specimens

Early diagnosis of Pneumocystis carinii pneumonia, a life-threatening complication in immunosuppressed patients, may lower morbidity and mortality. We have developed a one-tube nested PCR assay for the detection of P. carinii in respiratory specimens. Four primers were selected from the sequence of the small-subunit rRNA gene of P. carinii to amplify a 265-bp fragment, and their specificities for P. carinii were confirmed by both theoretical evaluations (by computer-assisted comparison with the sequences in GenBank) and empirical evaluations (with DNA from medically important fungi and diagnostic samples). The assay was optimized for routine diagnostic use. Processing of the clinical samples is rapid and simple (digestion with proteinase K directly in PCR buffer at room temperature in the presence of 10% Chelex 100 and no further purification steps). Bovine serum albumin (1 mg/ml) and glycerol (10%) in the amplification buffer reduced the number of samples inhibitory to the PCR, as assessed by control reactions containing a size-modified target. A total of 749 clinical specimens (312 bronchoalveolar lavage, 403 sputum or induced sputum, and 34 other specimens) from 507 patients (295 human immunodeficiency virus [HIV]-infected and 164 non-HIV-infected patients and 48 patients whose HIV status was unknown) were tested by PCR, and the results were compared with those of an indirect immunofluorescence assay (IFA). Concordant results were obtained for 732 samples (646 negative and 86 positive). There were 17 discrepant results: 12 were PCR positive and IFA negative, and 5 were PCR negative and IFA positive. After resolution of the discrepant results by review of the patients' clinical data, the sensitivity and specificity were 94.8 and 99.1%, respectively, for PCR and 93.8 and 100%, respectively, for IFA. In conclusion, the short procedure time and the technical ease of this PCR assay render it suitable for implementation in routine diagnostic laboratories.

Bacterial infections

Non-opportunistic bacterial infections are an important cause of morbidity and mortality for HIV-infected adults and children. Factors associated with increased risk of these include altered B- and T-cell function; altered phagocytic cell function; skin and mucous membrane defects; and use of indwelling vascular catheters, antibiotics, or cytotoxic agents. The pathogens encountered most frequently are S. aureus, S. pneumoniae, H. influenzae, Salmonella sp., and Pseudomonas aeruginosa. Less commonly encountered organisms include Rhodococcus equi, Listeria monocytogenes, Shigella sp., and Nocardia asteroides, Strategies for prevention as well as diagnosis and treatment of these are discussed.

HIV-associated respiratory diseases

The lungs of individuals infected with HIV are often affected by opportunistic infections and tumours; over two-thirds of patients have at least one respiratory episode during the course of their disease. Despite the availability of effective prophylaxis, infection with the fungus Pneumocystis carinii remains a common cause of respiratory disease. Bacterial infections, which occur more frequently in HIV-infected persons than in the general population, and tuberculosis are increasing causes of morbidity and mortality. Kaposi's sarcoma, the commonest HIV-associated malignancy, may affect the lungs in addition to the skin. Pulmonary involvement by non-Hodgkin lymphoma is common in those with disseminated disease.

Pulmonary complications of HIV disease: 10 year retrospective evaluation of yields from bronchoalveolar lavage, 1983-93

BACKGROUND

Pulmonary disease is a major contributor to morbidity and mortality in patients with HIV infection and AIDS. The aim of this study was to describe bronchoscopic findings and the spectrum of pulmonary pathogens in HIV seropositive patients undergoing investigation of respiratory disease over a 10 year period in a major UK referral centre.

METHODS

Recruitment was procedure based with data being captured when bronchoscopy was clinically indicated. Data were evaluated from 580 HIV seropositive patients (559 men, age 13-65 years) over a 10 year period from June 1983 to March 1993.

RESULTS

A total of 947 bronchoscopies was performed. The most frequent pulmonary pathogen isolated from bronchoalveolar lavage (BAL) fluid in 44% of all bronchoscopies was Pneumocystis carinii. Of all patients studied, 324 (55%) had at least one cytologically confirmed episode of P carinii pneumonia; this was AIDS defining in 219 (38%) of patients who underwent bronchoscopy. Between 1987 and 1993 the overall diagnostic yield from BAL fluid was 76%; 25% of all bronchoscopies yielded positive microbiological results, the most frequent isolates being Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas spp, and Haemophilus influenzae. Mycobacteria were identified in 8% of patients; M tuberculosis was the most common being identified in 3% of lavage samples and in 4% of patients. No drug-resistant M tuberculosis was found. Viral isolates (mainly cytomegalovirus) were identified in up to 31% of BAL fluid samples. Endobronchial Kaposi's sarcoma was seen in 15% of patients at bronchoscopy.

CONCLUSIONS

Of the 1956 newly diagnosed HIV seropositive patients receiving clinical care at St Mary's Hospital over this period, approximately 30% underwent bronchoscopy. Diagnostic rates for P carinii pneumonia, endobronchial Kaposi's sarcoma, and bacterial and mycobacterial infection have remained largely constant since 1989. Bronchoalveolar lavage produces high diagnostic yields generally, and P carinii pneumonia remains a common cause of pulmonary disease in these patients.

Cryptococcal pneumonia in patients with the acquired immunodeficiency syndrome

Infection with Cryptococcus neoformans occurs with increased frequency in patients with the human immunodeficiency virus (HIV). Despite the lungs being the portal of entry for the fungus the commonest presentation is with meningitis: Cryptococcal broncho pulmonary infection occurs less commonly. The chest radiographs of fourteen HIV positive patients with cryptococcal pneumonia were reviewed. The commonest radiographic abnormalities were interstitial infiltrates, (nine patients) and focal or widespread alveolar consolidation (seven patients). Ground glass shadowing, not previously described in cryptococcal pneumonia, occurred in six radiographs, miliary nodules in one, lymphadenopathy in four, and small pleural effusions in three. Two patients had a normal chest radiograph. In contrast to previous reports, we found alveolar consolidation and ground glass shadowing to be common and nodules and cavitation to be rare. Cryptococcal pneumonia should be considered in the differential diagnosis of Pneumocystis carinii pneumonia, bacterial pneumonia and miliary tuberculosis in HIV positive patients.

Bronchopulmonary infection with Pseudomonas aeruginosa in patients infected with human immunodeficiency virus

BACKGROUND

Pseudomonas aeruginosa infection is uncommon in HIV infected patients and is usually nosocomially acquired and associated with risk factors such as neutropenia or central lines. We have recently noted an increase in the number of respiratory isolates of Ps aeruginosa in hospitalised HIV positive patients and sought to describe the clinical correlates of this observation.

METHODS

A retrospective case notes review of HIV positive patients admitted to a specialist unit for respiratory investigations from January 1989 to December 1993 was undertaken in order to identify those with Ps aeruginosa respiratory infection and to describe associated risk factors, patterns of presentation and radiographic abnormalities.

RESULTS

Of 617 patients admitted 38 (6%) had Ps aeruginosa respiratory infection (notes were incomplete in 1 patient). All patients had advanced HIV disease; median CD4 = 0.02 x 10(9)/l. Two distinct presentations were seen; 9 patients had a fulminant course as part of a sepsis syndrome, 28 patients had an indolent presentation (18 had a single episode and 10 relapsed on one or more occasions, despite successful treatment of the initial episode). Infection was community acquired in 24 patients. Many patients had risk factors traditionally associated with Ps aeruginosa including neutropenia or indwelling central venous catheters, but 13 had no obvious risk factor. Most patients were receiving systemic pneumocystis prophylaxis and/or broad spectrum antibiotics; 20 had co-existent symptomatic sinus disease. A wide variety of chest radiographic abnormalities were seen including interstitial shadowing, mimicking pneumocystis pneumonia in 12 patients, lobar pneumonia in 2 and bronchial wall thickening in 13 patients.

CONCLUSIONS

Ps aeruginosa respiratory infection occurs with increased frequency in patients with advanced HIV disease; in a significant proportion infection is community acquired. Although recognised risk factors were present in two thirds of patients it appears that advanced HIV immunosuppression, use of systemic pneumocystis prophylaxis and/or broad spectrum antibiotics and sinus disease are important risk factors. The diagnosis should be considered in patients with advanced HIV disease who present with new respiratory symptoms.

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

Images

Exploration of the pulmonary circulation. Festschrift to Professor Donald Heath

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Granulomatous Pneumocystis carinii pneumonia: DNA amplification studies on bronchoscopic alveolar lavage samples

Three HIV positive subjects presented with symptoms and radiographic changes suggestive of Pneumocystis carinii pneumonia. Methenamine silver staining of bronchoscopic alveolar lavage (BAL) fluid was negative (from one sample in one patient and two samples in the other two patients). Open lung biopsy was performed because of uncertain clinical progress and diagnosis; all three patients were found to have multiple pulmonary granulomata encasing numerous P carinii organisms. DNA amplification, using P carinii specific oligonucleotides, was performed on stored bronchoscopic BAL samples. P carinii specific amplification product was detected by ethidium bromide staining after electrophoretic separation on agarose gel in one case, and by the more sensitive technique of oligohybridisation in all three cases. In granulomatous P carinii pneumonia organisms are rarely identified in bronchoscopic alveolar lavage samples using histochemical staining, but are detectable by DNA amplification, although not at levels which can be readily distinguished from low, subclinical infection.

Histologically atypical Pneumocystis carinii pneumonia

BACKGROUND

Infection with Pneumocystis carinii typically results in a pneumonia which histologically is seen to consist of an eosinophilic foamy alveolar exudate associated with a mild plasma cell interstitial infiltrate. Special stains show that cysts of P carinii lie within the alveolar exudate. Atypical histological appearances may occasionally be seen, including a granulomatous pneumonia and diffuse alveolar damage. In these patients the clinical presentation may be atypical and results of investigations negative unless lung biopsies are performed and tissue obtained for histological examination.

METHODS

The incidence and mode of presentation of histologically atypical pneumocystis pneumonia was studied in a cohort of HIV-I antibody positive patients.

RESULTS

Over a 30 month period 138 patients had pneumocystis pneumonia, of whom eight (6%) had atypical histological appearances which were diagnosed (after negative bronchoalveolar lavage) by open lung biopsy in five, percutaneous biopsy in one, and at post mortem examination in two. Atypical appearances included granulomatous inflammation in four patients, "pneumocystoma" in two (one also had extrapulmonary pneumocystosis), bronchiolitis obliterans organising pneumonia in one patient, diffuse alveolar damage and subpleural cysts in one (who also had intrapulmonary cytomegalovirus infection), and extrapulmonary pneumocystosis in two patients.

CONCLUSIONS

Various atypical histological appearances may be seen in pneumocystis pneumonia. Lung biopsy (either percutaneous or open) should be considered when bronchoalveolar lavage is repeatedly negative and evidence of P carinii should be sought, by use of special stains, in all lung biopsy material from HIV-I antibody positive patients.