Pulmonary complications of the acquired immunodeficiency syndrome: a clinicopathologic study of 70 cases

Quantifying Deaths from Aspergillosis in HIV Positive People

Aspergillus spp. are ubiquitous and cause severe infections in immunocompromised patients. Less is known about its incidence and prognosis in patients with HIV/AIDS. We reviewed the mortality of invasive aspergillosis in HIV/AIDS patients. Pubmed, Embase and Medline databases were used to search for articles. Studies were excluded if they contained other aspergillosis risk factors, no original or patient survival data or were not in English. From 747 articles published, 54 studies and case reports were identified following reading, published between 1985 and 2021, with 54% papers prior to 2000 reporting 853 patients from 16 countries, none from Africa. 707 (83%) patients died with an average time from diagnosis to death of 77.5 days. Postmortem diagnosis was seen in 21% of deaths recorded. A national series from France of 242 cases of invasive aspergillosis diagnosed in life recorded a 3 month mortality of 68% pre-ART, falling to 31% after introduction of ART and voriconazole. CD4 count was recorded in 39 studies and ranged from 2 to >1000 cells/mm3; only 8 patients (1.8%) had a CD4 > 100 cells/mm3. Aspergillosis occurs in patients with HIV/AIDS and associated with high mortality but its slow progression should allow diagnosis and treatment with improved outcome.

Outcome of Intensive Care in Patients with the Acquired Immunodeficiency Syndrome

The prognosis of patients who become critically ill due to complications of the acquired immunodeficiency syndrome (AIDS) is generally believed to be poor, but no detailed studies have substantiated this impression. We performed a retrospective analysis of patients with AIDS admitted to the Medical Special Care Unit (MSCU) at Mount Sinai Medical Center in New York over a 42-month period. Of 910 patients admitted to the MSCU, 35 (4% ) had AIDS. An additional patient admitted to the pediatric intensive care unit was included in the analysis.

Respiratory failure occurred in 31 patients (86% ) and was the most common problem necessitating admission. Twenty-five of these patients (69% ) had Pneumocystis carinii pneumonia. All 31 patients with respiratory failure required endotracheal intubation and mechanical ventilation, and 27 (87%) died during the same hospitalization. Pneumothorax requiring tube thoracostomy occurred in 6 of 31 patients receiving mechanical ventilatory support. Among the 4 mechanically ventilated survivors, only 2 patients remain alive. Intensive care unit intervention in patients with AIDS and respiratory failure is associated with a poor outcome and probably does not alter the ultimate course in most cases.

Undiagnosed HIV Presenting with Lymphoid Interstitial Pneumonitis

Undiagnosed or untreated human immunodeficiency virus infection can lead to devastating complications. We present a case of a 41-year-old woman who was found to have HIV-related lymphoid interstitial pneumonitis. LIP is uncommon, and its presentation can be quite similar to that of other chronic lung conditions. This case illustrates one of the possible protean manifestations of untreated HIV and is a sobering reminder of the need to screen all adults for HIV infection. Additionally, further invasive diagnostic testing may be required to guide therapy in patients with advanced acquired immune deficiency syndrome. This patient's LIP was likely related to long-standing unrecognized HIV disease.

The Impact of Open Lung Biopsy on Diffuse Pulmonary Infiltrates in Patients with AIDS

The evidence concerning open lung biopsy (OLB) for diffuse pulmonary infiltrates in patients with AIDS is limited. This study retrospectively evaluated the diagnostic and therapeutic yields of OLB compared with bronchoscopy for patients with AIDS with diffuse pulmonary infiltrate treated in the National Taiwan University Hospital from 1997 to 2004. There were 15 and 46 patients enrolled in the OLB and bronchoscopic groups in this study, respectively. As compared with the bronchoscopic group, patients from the OLB group had a higher chance of acquiring a specific diagnosis and possible change of therapy (73 vs 32.6% and 60 vs 21.7%, respectively; P < 0.05). There were two (13.3%) patients with prolonged air leak (greater than 7 days) in the OLB group, whereas four patients (8.7%) had procedure-related complications in the bronchoscopic group. There was no procedure-related mortality in the OLB group. This study demonstrated that OLB can be safely performed in select patients and provide a superior diagnostic and therapeutic benefit compared with bronchoscopy for diffuse pulmonary infiltrates in patients with AIDS. This procedure should be performed early in the clinical course to avoid irreversible clinical deterioration of the patients with severe illness.

Fungal Infections

The incidence of invasive fungal infections has increased dramatically over the past two decades, mostly due to an increase in the number of immunocompromised patients.1–4 Patients who undergo chemotherapy for a variety of diseases, patients with organ transplants, and patients with the acquired immune deficiency syndrome have contributed most to the increase in fungal infections.5 The actual incidence of invasive fungal infections in transplant patients ranges from 15% to 25% in bone marrow transplant recipients to 5% to 42% in solid organ transplant recipients.6,7 The most frequently encountered are Aspergillus species, followed by Cryptococcus and Candida species. Fungal infections are also associated with a higher mortality than either bacterial or viral infections in these patient populations. This is because of the limited number of available therapies, dose-limiting toxicities of the antifungal drugs, fewer symptoms due to lack of inflammatory response, and the lack of sensitive tests to aid in the diagnosis of invasive fungal infections.1 A study of patients with fungal infections admitted to a university-affiliated hospital indicated that community-acquired infections are becoming a serious problem; 67% of the 140 patients had community-acquired fungal pneumonia.8

Characterization of the tuberculous granuloma in murine and human lungs: cellular composition and relative tissue oxygen tension

The granulomatous reaction is the hallmark of the host response to infection with Mycobacterium tuberculosis. Despite its apparent importance to host defence against the tubercle bacillus, the granulomatous response remains to be completely defined. The present study used histological, immunohistochemical and flow-cytometric analyses to characterize pulmonic granulomatous tissues of tuberculous mice and humans. The kinetics of recruitment of neutrophils, macrophages, dendritic cells, and T and B lymphocytes into the lungs of mice infected aerogenically with the virulent Erdman strain of M. tuberculosis was evaluated in detail in both the acute and persistent phase of infection. A hypoxia-sensing compound based on the 2-nitroimidazole structure (EF5), together with immunohistochemical studies targeting endothelial cells were used to examine the relative oxygen tension in tuberculous granulomatous tissues in mice. The results have provided evidence that: (i) the granulomatous tissues are a highly organized structure whose formation is regulated by orderly recruitment of specific immune cells exhibiting distinct spatial relationship with one another; (ii) the granulomatous reaction, at least in the mouse, may represent an exaggerated response to the tubercle bacillus that can play a role in the development of immunopathology; (iii) B lymphoid aggregates are a prominent feature in both murine and human granulomatous tissues, although the immune cells that are most prominently associated with these clusters vary among the two species; (iv) murine tuberculous granulomatous tissues are relatively aerobic, suggesting that mouse models of persistent tuberculosis may not be suitable for the study of any hypoxic response of M. tuberculosis.

Lymphocytic interstitial pneumonitis in HIV infected adults

OBJECTIVES

To describe current knowledge on the aetiology, pathology, presentation, diagnosis, and treatment of lymphocytic interstitial pneumonitis in HIV infected adults.

METHODS

A Medline search was performed using the key words "HIV," "pneumonitis," and "lymphocytes." A further search was performed with the MESH heading "interstitial lung disorders." Related articles were also searched using Pubmed.

RESULTS

Lymphocytic interstitial pneumonitis is a common complication in HIV infected children. In adults it is uncommon and is described most commonly among black African and Afro-Caribbean patients. The aetiology and pathogenesis of lymphocytic interstitial pneumonitis in HIV infection is not clear. The clinical and radiological presentations may be indistinguishable from Pneumocystis carinii infection and a lung biopsy is necessary to establish the diagnosis. Recent evidence suggests that lymphocytic interstitial pneumonitis in HIV infected patients may respond to combination antiretroviral therapy with dramatic improvements in clinical and radiological abnormalities.

CONCLUSION

Lymphocytic interstitial pneumonitis in HIV infected patients is a treatable condition. This condition should be considered in HIV infected patients presenting with respiratory symptoms as they may gain considerable benefit from antiretroviral therapy.

Prospective study of etiologic agents of community-acquired pneumonia in patients with HIV infection

OBJECTIVES

To study prospectively HIV-positive patients admitted to the hospital because of pneumonia by extensive laboratory tests to determine specific microbiologic diagnoses and to establish the best clinical diagnosis after review of all available data by expert clinicians.

METHODS

Patients admitted to one of two hospitals had extensive questionnaires completed and defined diagnostic tests performed on blood, sputum, urine and bronchoalveolar lavage specimens, when available.

RESULTS

A total of 230 patients had a diagnosis of pneumonia verified. A definite or probable etiologic diagnosis was made in 155 (67%) of these patients. Pneumocystis carinii caused 35% of all cases of pneumonia. Twenty-seven percent of cases of pneumonia with a single etiology had a definite or probable bacterial etiology. 'Atypical agents' were distinctly uncommon. Few clinical or laboratory parameters could differentiate specific etiologies.

CONCLUSIONS

P. carinii continues to be a common cause of pneumonia in these patients. The rarity of 'atypical agents' could simplify the empiric approach to therapy. Despite the use of extensive testing we did not find a definite etiology in a large number of cases.

Primary pulmonary mucosa-associated lymphoid tissue lymphoma with associated fungal ball in a patient with human immunodeficiency virus infection

We describe a case of primary mucosa-associated lymphoid tissue lymphoma of the lung in a 44-year-old man with human immunodeficiency virus. Low-grade pulmonary lymphomas in human immunodeficiency virus-positive patients are rare and are described most commonly in pediatric patients. The gross, histologic, and molecular features of this unusual case are described.

Role of bronchoscopy in AIDS

The differential diagnosis of pulmonary disorders in the HIV-infected individual is broad. Clinical features and chest radiographs may point towards a diagnosis but cannot reliably establish one. It is important to know the conditions in which bronchoscopy, BAL, and TBB are likely to be diagnostic, just as it is to know when other invasive or noninvasive procedures may be more useful. Finally, the incidence of transmission of infections such as tuberculosis during bronchoscopy and cross-contamination of patients with an improperly sterilized bronchoscope, cannot be overemphasized.

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.

Pathology of human immunodeficiency virus infection: noninfectious conditions

Diagnostic anatomic pathologists play a crucial role in the battle against acquired immunodeficiency syndrome (AIDS). Not only are they intimately involved in the treatment of individual patients with human immunodeficiency virus (HIV) infection, but also they make important observations that result in the expansion of the scientific understanding of its pathogenesis. Pathologists studying tissue from patients with HIV infection should be familiar with the conditions to which these patients are susceptible. Although opportunistic infections are important causes of morbidity and mortality, noninfectious conditions frequently make substantial contributions to the disease course. Patients with HIV infection may be at increased risk for neoplastic disease. They do not, however, have an increased incidence of the most common tumors affecting the general population, such as breast, colon, and prostate carcinoma. Immunodeficiency results in increased susceptibility to malignant neoplasms, both by decreased immunologic response to abnormal cells and increased susceptibility to infection by viruses. All of the malignant neoplastic diseases that are Centers for Disease Control and Prevention (CDC) AIDS indicator conditions have been shown to have an association with a virus: Kaposi sarcoma (KS) with herpes hominis virus 8 (HHV-8), malignant lymphoma with Epstein-Barr virus (EBV), and cervical carcinoma with human papilloma virus (HPV). Patients with HIV infection also can develop reactive processes that are attributable to direct effects of HIV or immune system alterations. Such conditions include salivary gland cystic lymphoepithelial lesion, lymphadenopathy, lymphocytic interstitial pneumonitis, encephalopathy, enteropathy, nephropathy, hepatic conditions, dermatologic conditions and anemia.

The pulmonary manifestations of AIDS-related non-Hodgkin's lymphoma

STUDY OBJECTIVE

To describe the clinical, radiographic, and autopsy features of AIDS-related non-Hodgkin's Iymphoma (NHL) with pulmonary involvement.

DESIGN

Retrospective series of patients with HIV infection and NHL with pathologically documented lung or pleural involvement.

SETTING

A university and a county hospital in San Francisco.

PATIENTS

Thirty-eight patients with HIV infection and NHL involving the lungs or pleura.

RESULTS

Most patients had respiratory symptoms (87%) and signs (84%). The majority of patients had advanced HIV infection, with a mean CD4 count of 67 (+/- 65). The most common laboratory abnormalities were elevated lactate dehydrogenase value (89%), elevated erythrocyte sedimentation rate (94%), hematologic abnormalities (95%), and widened alveolar-arterial gradient (89%). Thoracic CT revealed pulmonary nodules (50%), lobar infiltrates (27%), and lung mass (19%) as the most common parenchymal abnormalities. Pleural effusion (68%) and thoracic lymphadenopathy (54%) were unexpectedly common. Autopsy confirmed the high prevalence of pulmonary nodules (30%), airspace disease (35%), and lung mass (25%). Pleural effusions (65%) and thoracic lymphadenopathy (60%) were also common at autopsy. The respiratory system was the most common extranodal site (71%) in patients with AIDS-related NHL undergoing autopsy. Of the bronchoscopic procedures performed, transbronchial biopsy had the highest diagnostic yield (58%) for lymphoma. BAL and bronchial brushing were never diagnostic. Pleural fluid cytologic study and open lung biopsy specimens also had high diagnostic yields (75% each).

CONCLUSIONS

The lung is a common extranodal site in AIDS-related NHL. NHL with pulmonary involvement occurs primarily in patients with advanced HIV infection. Most patients have nodules, infiltrates, or masses by thoracic imaging and autopsy. Thoracic lymphadenopathy is much more common than previously believed. Transbronchial biopsy, pleural fluid cytologic study, and open lung biopsy are the most useful diagnostic procedures.

Morphological study of bacteria of the respiratory system using fluorescence microscopy of Papanicolaou-stained smears with special regard to the identification of Mycobacteria sp

In Papanicolaou-stained smears certain structures such as nucleoli, Pneumocystis carinii, Charcot-Leyden crystals, bacteria and fungi show a brilliant fluorescence. The morphological characteristics of microorganisms which can be detected by this system, especially mycobacteria, are described. This screening method offers the possibility of providing the clinician with a provisional diagnosis within hours. Proof of the nature of the organisms should be obtained by culture.

Intrathoracic Kaposi's sarcoma. CT findings

AIM

To describe the thin CT scans findings in AIDS patients with intrathoracic Kaposi's sarcoma (KS).

MATERIAL AND METHODS

Fifty-three CT scans of patients with KS were retrospectively reviewed. The diagnosis of intrathoracic KS was established histologically (n = 17) or on the association of skin KS and the visualization of characteristic endobronchial lesions (n = 36). CT scans were performed with thin slices (2 mm) obtained at 10-mm intervals, and a 512 x 512 reconstruction matrix. No patients had Pneumocystis carinii pneumonia within the 3 months preceding the CT scan examination.

RESULTS

Numerous nodules (n = 42), tumoral masses (n = 28), bronchovascular pathways thickening (n = 35), and pleural effusions (n = 28) were the most frequent patterns. Septal lines (n = 15), ground-glass opacities (n = 3), and mediastinal adenopathies (n = 8) were not frequent.

CONCLUSION

Numerous nodules, tumoral masses, bronchovascular pathways thickening, and bilateral pleural effusions were the main signs of intrathoracic KS; their association (66%) is very characteristic. An opportunistic infection or mycobacteriosis must be sought if the thin CT scans reveal ground-glass opacities and/or mediastinal adenopathies.

Cytomegalovirus infection induces high levels of cyclins, phosphorylated Rb, and p53, leading to cell cycle arrest

Human cytomegalovirus (HCMV) infection stimulates cellular DNA synthesis and causes chromosomal damage. Because such events likely affect cellular proliferation, we investigated the impact of HCMV infection on key components of the cell cycle. Early after infection, HCMV induced elevated levels of cyclin E, cyclin E-associated kinase activity, and two tumor suppressor proteins, p53 and the retinoblastoma gene product (Rb). The steady-state concentration of Rb continued to rise throughout the infection, with most of the protein remaining in the highly phosphorylated form. At early times, HCMV infection also induced cyclin B accumulation, which was associated with a significant increase in mitosis-promoting factor activity as the infection progresses. In contrast, the levels of cyclin A and cyclin A-associated kinase activity increased only at late times in the infection, and the kinetics were delayed relative to those for cyclins E and B. Analysis of the cellular DNA content in the infected cells by flow cytometry showed a progressive shift of the cells from the G1 to the S and G2/M phases of the cell cycle, leading to an accumulation of aneuploid cells at late times. We propose that these HCMV-mediated perturbations result in cell cycle arrest in G2/M.

Radiographic manifestations of AIDS related lymphoma in the thorax

Intrathoracic disease in AIDS-related lymphoma (ARL) produces a range of radiographic appearances. This study aimed to determine the frequency, distribution and characteristics of these appearances. The case notes and findings on imaging of 116 consecutive cases of ARL were reviewed retrospectively. In 52 cases there were abnormalities present on chest imaging (chest radiography or chest CT scanning). In 20 patients abnormalities were judged to be due to lymphomatous involvement and in 15 cases the thorax was the major site of disease. Correlation with biopsy results from thoracic disease (9), other disease (5), or evidence of response to treatment (6) was made. The most frequent imaging findings were pleural or intrapulmonary masses (7), frequently peripheral and sometimes with cavitation. In one case this simulated mycetoma formation. Pleural effusions and mediastinal lymph nodes were also frequently present, either alone or in combination. AIDS-related lymphoma uncommonly involves the chest as a major site of disease. A pleural or intrapulmonary mass with cavitation may represent the only site of disease and in these cases CT guided biopsy is likely to provide the histological diagnosis.

Bacterial pneumonia in adult patients with HIV infection

Patients with HIV infection are at increased risk for community-acquired bacterial pneumonias, due in part to their defects in B-cell function. Streptococcus pneumoniae is the commonest cause of community-acquired pneumonia, with the second most common bacterial agent being Haemophilus influenzae. These two organisms account for about two-thirds of community-acquired bacterial pneumonias. Frequently bacterial pneumonias appear difficult to distinguish from Pneumocystis carinii pneumonia or other opportunistic lung infections, because of their atypical clinical and radiologic presentations. Community-acquired pneumonias may be recurrent but have low fatality rates. In comparison, nosocomial pneumonias occur primarily in patients with AIDS and are usually due to Staphylococcus aureus, Pseudomonas aeruginosa and other aerobic gram-negative bacilli. Nosocomial pneumonias have high fatality rates. S.aureus is an important cause of morbidity and mortality in patients with AIDS and has emerged as a secondary opportunist in lungs of patients with opportunistic diseases. While appropriate laboratory study is being done, empiric antibiotic therapy should be directed against the microorganisms above described.

The role of bronchoscopy in the diagnosis and treatment of pulmonary disease in HIV-infected patients

BACKGROUND

Pulmonary disease is the most common reason for presentation and the major cause of death in HIV-infected patients. There has been an evolution in the optimal approach to the investigation of a pulmonary infiltrate in HIV-infected patients since the introduction of induced sputum for the diagnosis of Pneumocystis carinii pneumonia (PCP).

AIMS

To evaluate the usefulness of flexible fibreoptic bronchoscopy (FFB), bronchoalveolar lavage (BAL), transbronchial biopsy (TBB) and bronchial brushings (BB) in the diagnosis of pulmonary disease in HIV-infected patients and to examine the effect of FFB on changes in therapy and survival.

METHODS

The histories of all HIV-infected patients referred to Fairfield Hospital for FFB between January 1990 and June 1993 were examined retrospectively.

RESULTS

Forty-two FFB were performed on 41 patients (40 male and one female). Definitive diagnoses made at FFB included Kaposi's sarcoma (KS) (n = 9), invasive aspergillosis (n = 5), PCP (n = 4), Mycobacterium avium complex (MAC) pneumonia (n = 2), cytomegalovirus (CMV) pneumonia (n = 1), Cryptococcus neoformans pneumonia (n = 1), microsporidium (n = 1) and Pseudomonas aeruginosa pneumonia (n = 1). TBB and BB did not provide a diagnosis for diseases not seen macroscopically at FFB or diagnosed by BAL. FFB findings altered diagnosis in 21/42 (50%) presentations and changed therapy in 26/42 (62%) cases.

CONCLUSIONS

FFB together with BAL altered the working diagnosis and changed therapy in a significant number of patients. TBB and BB should not be routinely performed in all patients as these procedures are of limited value in this setting.

Infections in children with human immunodeficiency virus/acquired immunodeficiency syndrome: an autopsy study of 30 cases in south Florida, 1990-1993

Thirty autopsies performed on infants and children with HIV infection and/or AIDS were reviewed for the presence and type of infection. Twenty-six (87%) demonstrated evidence of infection in addition to HIV at the time of postmortem examination. Pathogenic bacterial infectious were the most frequently encountered, seen in 15 of the cases. Nine of the 15 (60%) were due to gram-negative rods, most commonly Pseudomonas aeruginosa. Infections with gram-negative organisms often involved multiple organ systems and were frequently undiagnosed both pre- and postmortem because of variability in culture results and difficulties in identification both clinically and in tissue sections. Discussion is presented of unusual staining characteristics and filamentous morphology found with these pathogens. Other pathogenic bacteria encountered were Klebsiella pneumoniae, Escherichia coli, Enterobacter sp., and Staphylococcus. Fungal infections due to Candida species were present in nine cases (31%) but were invasive in only two of these. One instance of Aspergillus meningo-encephalitis was noted. Proven viral infections were present in five children (three cytomegalovirus, one herpes simplex, and one adenovirus). Pneumocystis carinii pneumonia was diagnosed in five of the patients (17%), and one instance of disseminated Mycobacterium avium-intracellulare was encountered.

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

Images

Exploration of the pulmonary circulation. Festschrift to Professor Donald Heath

Images

Pulmonary aspergillosis in patients with AIDS. Clinical and radiographic correlations

OBJECTIVE

To evaluate the clinical and radiographic features of pulmonary aspergillosis as they present in AIDS patients; in particular, to determine similarities and differences between Aspergillus infection in patients with AIDS vs those without AIDS.

SUBJECTS AND METHODS

Six new cases of confirmed or probable pulmonary aspergillosis were discovered during a search of hospital records. These are reviewed with 30 previously reported cases with special attention to radiographic appearance of disease and how radiographic appearance influences clinical outcome.

RESULTS

Symptoms of pulmonary aspergillosis in AIDS were nonspecific, most often including fever, cough, and dyspnea, and less commonly, chest pain or hemoptysis. Major risk factors for the development of pulmonary aspergillosis in patients with AIDS were steroid administration and neutropenia. Neutropenia was often a complication of therapies for AIDS, in particular, ganciclovir and zidovudine. Radiographic appearance of disease could be divided into three general categories. One third of the patients (13/36) presented with cavitary upper lobe disease resembling noninvasive or chronic necrotizing aspergillosis. Fatal hemoptysis occurred in 42 percent of patients with this form of disease. Twenty-two percent (8/36) of the cases presented as a nondescript focal alveolar opacity similar to invasive aspergillosis. In several patients, the focal infiltrate remained stable for several months, a feature that is unusual for aspergillosis in non-AIDS patients. The air crescent sign was present in none of the 36 reported cases. Patients with only focal disease had the best prognosis of patients with pulmonary aspergillosis. Bilateral alveolar or interstitial disease similar to invasive aspergillosis was present in 23 percent (9/36) of the patients. Bilateral disease appears to be a marker for disseminated infection and was associated with a high mortality due to aspergillosis. Two new forms of bronchial aspergillosis (5/36 cases) have been described previously. These patients presented with either obstructing fungal casts or bronchial pseudomembranes demonstrated bronchoscopically. In some patients with the bronchial forms of aspergillosis, transient alveolar opacities were seen on chest radiographs. These opacities may represent regions of atelectasis due to airway obstruction. One patient who had bilateral pneumothoraces without parenchymal opacities did not correspond to any of the three previously mentioned categories. Mortality due to aspergillosis was greater than 50 percent among AIDS patients. Death was subsequent to fatal hemoptysis or widespread pulmonary or systemic infection.

CONCLUSION

Unlike other risk groups that tend to contract only one form of pulmonary aspergillosis, AIDS patients can develop the whole spectrum of aspergillosis-related pulmonary disorders, including chronic cavitary, invasive, and bronchial forms of aspergillosis. Clinical symptoms are nonspecific and major risk factors include neutropenia, which is often a side effect of various therapies for AIDS, and steroid administration. Patients with the chronic cavitary form of disease have an unusually high mortality due to fatal hemoptysis. Patients with bilateral pulmonary infiltrates and aspergillosis have a high mortality due to disseminated infection.

Effect of selected cytokines on the replication of Corynebacterium pseudotuberculosis and ovine lentiviruses in pulmonary macrophages

Opportunistic bacterial pathogens that induce monokine secretion by pulmonary alveolar macrophages (PAM) are frequently encountered complicating factors in lentivirus-associated pneumonias in ungulates and man. We examined the effect of selected cytokines on the replication of Corynebacterium pseudotuberculosis and ovine lentivirus (OvLV) in ovine PAM. Recombinant bovine (rBo) IL 1 beta, rBoIL-2, rBo interferon-gamma (IFN gamma) and rBoTNF alpha, alone and in combination at physiological doses had no apparent effect on the extracellular growth of C. pseudotuberculosis, compared with the growth of the pathogen in medium alone. Untreated ovine PAM, derived from bronchoalveolar lavage, were found to substantially reduce, but not eliminate the growth of C. pseudotuberculosis in culture. This bactericidal effect was neither enhanced nor inhibited by pretreatment of PAM with the recombinant bovine cytokines or low doses of LPS that induce monokines. In contrast, addition of rBoTNF alpha or rBoIL-1 beta, at physiological doses, at the initiation of, or on Day 4, after OvLV infection resulted in a significant increase in viral replication in PAM, as measured in an antigen capture assay for OvLV p25, compared with untreated infected cells. This effect was more pronounced with lower levels of infecting OvLV, and, in the case of TNF alpha, was abrogated by preincubation of the cytokine with specific anti-serum. Conversely, in most instances, inclusion of rBoIFN alpha in OvLV-infected PAM cultures resulted in a significant decrease in viral replication. These results suggest that these soluble mediators that are probably secreted in response to C. pseudotuberculosis infection may have little direct effect on the extra- or intracellular survival of the bacteria in the lung, but may modulate lentiviral replication and, by extension, disease expression, in sheep with dual infection.

Ultrastructural study of hepatic granulomas induced by Cryptococcus neoformans by quick-freezing and deep-etching method

The ultrastructure of hepatic granulomas induced by Cryptococcus (C.) neoformans was studied by a quick-freezing and deep-etching (QF-DE) method. Viable yeast cells were inoculated intravenously into rats and the livers were prepared for QF-DE replicas. Two cytoskeletal components were identified in the cytoplasm of macrophages composing the cryptococcal granulomas. These were: intermediate filaments, mainly located in the perinuclear region, and actin filaments, which were extensively decorated with myosin subfragment 1 (S1) and formed networks in the peripheral portion of the cytoplasm. In addition, two types of macrophage pseudopodia were observed in the granulomas. These were cobble stone-like pseudopodia at the yeast-macrophages contract areas, and thin, long and occasionally interdigitating pseudopodia in which actin filaments were consistently observed. Dense networks of actin filaments were also seen in pseudopodia protruding into the tight structure of the capsule of C. neoformans. These results suggest a role for actin filaments as one of the main factors in the force generating system of the phagocytic process.

CT manifestation of non-Hodgkin's lymphoma as a solitary pulmonary nodule in a patient with acquired immunodeficiency syndrome

We present a case of acquired immunodeficiency syndrome with primary pulmonary non-Hodgkin's lymphoma that manifested as a solitary pleura-based mass lesion. Its differentiation from an infectious process imposed a diagnostic dilemma. The importance of awareness of such an entity for earlier diagnosis is stressed.

Invasive aspergillosis in patients with acquired immunodeficiency syndrome: report of 33 cases. French Cooperative Study Group on Aspergillosis in AIDS

PURPOSE

Acquired immunodeficiency syndrome (AIDS)-associated invasive aspergillosis (IA) is a rare condition, which is mainly reported as isolated cases either antemortem or at autopsy. The role of AIDS itself is controversial, because many of the reported patients exhibited the classic risk factors such as neutropenia and steroid therapy. The aims of this study were to report 33 patients with IA during AIDS and their outcome, focusing on the risk factors and the value of diagnostic procedures.

PATIENTS AND METHODS

Thirty-three patients from 17 different medical centers in France were retrospectively included in the study. For pulmonary IA, we defined two types of patients: those with "confirmed IA," describing all the patients with histologically proven disease, and those with "probable IA," who had the development of a new pulmonary infiltrate on chest radiograph and a positive bronchoalveolar lavage (BAL) fluid culture for Aspergillus species without identification of other pathogens. For extrapulmonary IA, the diagnostic criteria included both positive histology and culture.

RESULTS

Of the 33 cases included in this series, 91% were recorded during the last 3 years (1989 to 1991), suggesting that aspergillosis is an emerging complication in AIDS. Approximately 50% of the patients did not exhibit any classic risk factor, i.e., neutropenia and steroid treatment; almost all patients had a CD4 cell count less than 50/mm3. The mycologic culture from BAL was the method of choice for the diagnosis of invasive pulmonary disease because it was known to correlate well with histologic findings obtained either antemortem or postmortem. Of 28 patients with a positive BAL culture for Aspergillus, 15 underwent a biopsy or autopsy and 14 were positive at histology. Serum antigen detection was positive in only 4 of 16 tested patients. Clinical and radiologic signs did not differ from those observed in neutropenic patients without human immunodeficiency virus, except for the higher incidence of neurologic complications in AIDS. Interestingly, we observed three cases of invasive necrotizing tracheobronchial aspergillosis with acute dyspnea and wheezing. The use of amphotericin B (0.5 mg/kg/d) and/or itraconazole (200 to 600 mg/d) was most often unsuccessful. Only four patients experienced clinical and radiologic improvement. The mean interval between the diagnosis of IA and death was 8 weeks (range: 3 days to 13 months).

CONCLUSIONS

This study suggests that aspergillosis is an important life-threatening condition in the advanced stage of AIDS. It requires an early diagnosis with BAL fluid culture and careful therapeutic evaluation.

Pulmonary lymphoproliferative disorders

Pulmonary lymphoproliferative disorders are a diverse group of conditions that primarily or secondarily involve the lungs. Modern diagnostic modalities, including immunologic and molecular genetics techniques, have contributed substantially to the continuously evolving understanding of these complex lesions. In this review, we classified pulmonary lymphoproliferative disorders into benign, intermediate or indeterminate, and malignant categories and described the clinical, radiographic, and pathologic features for the entire spectrum. Our emphasis is on the clinical findings and the role of tissue biopsy as well as ancillary techniques in diagnosis. Various treatments and expected responses are also discussed.

Bronchoscopy versus empirical therapy in HIV-infected patients with presumptive Pneumocystis carinii pneumonia. A decision analysis

The outcomes of alternative strategies for the management of pulmonary complications in patients infected with the human immunodeficiency virus (HIV) and with suspected Pneumocystis carinii pneumonia were compared using a decision analysis model. A decision tree was constructed using baseline probabilities derived from published data and expert opinion. The case scenario analyzed was that of a patient not currently receiving anti-Pneumocystis prophylaxis who presents with moderate pulmonary symptoms and fulfills the Centers for Disease Control (CDC) criteria for presumptive P. carinii pneumonia. Two strategies were compared: (1) early bronchoscopy with appropriate therapy based on the results, and (2) empiric treatment for P. carinii (trimethoprim/sulfamethoxazole or pentamidine, and steroids) with delayed bronchoscopy in those not responding to 5 days of empiric therapy. The expected 1-month survival rate (with and without quality of life adjustment) was found to be essentially the same for the two strategies using the baseline probabilities, and the decision remained a toss-up within the clinically relevant range of published probabilities for P. carinii pneumonia in patients fulfilling the CDC criteria. Because early bronchoscopy does not offer any additional survival benefits and is associated with greater costs and disutility, empiric therapy would appear to be the superior management strategy in this scenario.

A life-threatening tracheal localization of lymphoma in a patient with AIDS

Lymphoma is a frequent complication of HIV infection, but we report a rare localization in the subglottic tracheal area. A case of tracheal stenosis due to lymphoma in an HIV-infected patient is presented. The main complaint was severe dyspnea. Chemotherapy was ineffective but radiotherapy improved the patient's condition and increased the caliber of the tracheal lumen.

Role of open lung biopsy in diagnosing pulmonary complications of AIDS

Over a 4-year period, 25 patients with pulmonary complications of acquired immunodeficiency syndrome underwent open lung biopsy for diagnosis. Results of the biopsy led to a change in therapy in 15, and of this group, 8 patients improved clinically and were discharged. We believe that a select group of acquired immunodeficiency syndrome patients with pulmonary disease will benefit from open lung biopsy. Our indications for open lung biopsy are (1) a nondiagnostic bronchoscopy, (2) failed medical therapy after a diagnostic bronchoscopy, (3) failed empiric medical therapy after a nondiagnostic bronchoscopy or after a second nondiagnostic bronchoscopy, and (4) when any of the forementioned are accompanied with a worsening chest roentgenogram. Patients with acquired immunodeficiency syndrome who have a deteriorating respiratory status or require mechanical ventilation should not undergo open lung biopsy.

Radiology of AIDS in the pediatric patient

The Acquired Immunodeficiency Syndrome (AIDS) has involved the pediatric age group and is especially prevalent in babies born of mothers who are intravenous drug abusers or prostitutes. Approximately 30% of children born to mothers who are seropositive for the human immunodeficiency virus (HIV) will develop HIV infection. There are several important differences in children and adults with AIDS. The incubation period of the disease is shorter, and initial clinical manifestations occur earlier in children. In addition, certain infections are more common in children, and the different types of malignancy, especially Kaposi's sarcoma, are unusual in the pediatric age group. The altered immune system involves both T cells and humoral immunity and increases susceptibility to a variety of infections, particularly opportunistic organisms. In this publication the complications of pediatric AIDS involving the lungs, cardiovascular system, gastrointestinal tract, genitourinary system, and neurological system are described. The most common pulmonary complications in our experience are Pneumocystis carinii pneumonia and pulmonary lymphoid hyperplasia. The spectrum of cardiovascular involvement in pediatric AIDS includes myocarditis, pericarditis, and infectious endocarditis. Gastrointestinal tract involvement is usually due to opportunistic organisms that produce esophagitis, gastritis, and colitis. Abdominal lymphadenopathy is a common finding either due to disseminating Mycobacterium avium-intracellulare infection or nonspecific lymphadenopathy. Although cholangitis is more commonly seen in adults, it may occur in children with AIDS and, in most cases, is due to related opportunistic infections. Genitourinary infections may be the first evidence of HIV disease. Cystitis, pyelonephritis, renal abscesses, and nephropathy with renal insufficiency are complications of pediatric AIDS. A variety of neurological abnormalities may occur in pediatric AIDS. The most common cause of neurological dysfunction in children with AIDS is HIV neuropathy. We present the many complications of AIDS in children demonstrated by a variety of imaging modalities, emphasizing the importance of diagnostic imaging in children with this disease.

Medical management of AIDS patients. Bacterial and fungal infections

The rapid and thus far generally inexorable rise in HIV infections has led to a series of opportunistic infection that includes those caused by bacteria, yeasts, and members of the Eumycetes. The infections range in prevalence from occasional to highly prevalent, in severity from trivial to fatal, and in anatomic areas involved from local to disseminated. They occur as isolated, concurrent, or sequential infections with regard to other opportunistic diseases. Some vary in their geographic distribution. They may be newly acquired or reactivated and occur early or late in the course of HIV infection. Bacterial infections are usually easily treated, although they frequently disseminate and often recur after seemingly appropriate treatment. In contrast, all but the mildest fungal infections are difficult to treat and even more difficult or impossible to eradicate. The diagnosis of bacterial and fungal infections begins with clinical suspicion and involves relatively standard methodology. Treatment of the systemic mycoses and some bacterial infections in HIV infected patients is punctuated by exaggerated side effects of therapy, frequent relapses, and the need for maintenance suppressive therapy.

Ultrastructural pathology of human immunodeficiency virus infection

The electron microscope has been used with great skill in many aspects of the acquired immunodeficiency syndrome. It has played a critical role in classifying the human immunodeficiency virus, in characterizing the morphogenesis and gene products of the virus, and in elucidating the host cell targets and interactions. With the aid of the electron microscope, new opportunistic pathogens are being identified, and particularly difficult diagnoses are being made. Extrapolations from observations made at the ultrastructural level to the light microscopic level have provided criteria for the diagnosis of several infectious agents. As with any powerful scientific tool, observations must be interpreted with great care by scientists experienced in electron microscopy.

Lentivirus-induced pulmonary lesions in rhesus monkeys (Macaca mulatta) infected with simian immunodeficiency virus

Necropsy reports from 28 rhesus monkeys that had been experimentally infected with simian immunodeficiency virus (SIV) and that were free of cytomegalovirus were reviewed. Lung sections from 24 of these monkeys that had no etiologic agent other than SIV detected in the lung were studied in detail by histopathologic, immunohistochemical, and electron microscopic examination and by in situ hybridization. Fourteen of the monkeys were part of a serial euthanasia study, while others were euthanatized after they became moribund. The following lesions were detected: perivascular inflammation, vasculitis, interstitial pneumonia, syncytial cells, hemorrhage, fibrin exudation, and pleural fibrosis. Perivascular inflammation was the most frequent lesion and occurred as early as 2 weeks after inoculation. Severe pneumonia and numerous syncytial cells were seen only in animals euthanatized because they had become moribund. The lesions appeared to be directly due to SIV infection. SIV antigens, RNA, and virions were detected in syncytial cells and macrophages by immunohistochemical examination, in situ hybridization, and transmission electron microscopic examination, respectively. The amount of virus present was correlated with the severity of the lesions. The SIV-induced lesions were different from those of the lymphocytic interstitial pneumonia, which occurs in human immunodeficiency virus-infected children and in ovine lentivirus-infected sheep and goats.

Invasive aspergillosis in AIDS

Invasive aspergillosis (IA) is a rare infection in patients with the Acquired Immune Deficiency Syndrome (AIDS). We report the first Australian cases of histologically and microbiologically proven IA diagnosed antemortem in AIDS patients. We also describe the first case of laryngeal involvement and the unusual case of a pneumothorax due to IA. These three cases illustrate the varied clinical and pathological features of IA in AIDS and highlight some of the difficulties in diagnosis and treatment. The infections occurred in the setting of advanced immunodeficiency and multiple opportunistic infections and responded poorly to treatment.

Differential induction of tumor necrosis factor alpha in ovine pulmonary alveolar macrophages following infection with Corynebacterium pseudotuberculosis, Pasteurella haemolytica, or lentiviruses

Soluble mediators such as tumor necrosis factor alpha (TNF-alpha) may be important in the pathogenesis of many chronic pulmonary infections. We examined the ability of Corynebacterium pseudotuberculosis, Pasteurella haemolytica, and ovine lentiviruses (OvLV) to induce TNF-alpha secretion by pulmonary alveolar macrophages (PAM). Bronchoalveolar lavage cells, composed of greater than 90% PAM, were obtained from normal sheep. Bronchoalveolar lavage cells were cultured for 2, 24, 48, 72, or 168 h in endotoxin-free RPMI medium (with 10% autologous serum) or in medium containing one of the following additives: lipopolysaccharide, 1-micron polystyrene beads, C. pseudotuberculosis, P. haemolytica, or one of two plaque-cloned OvLV, 85/28 or 85/34. Lipopolysaccharide, C. pseudotuberculosis, and P. haemolytica induced TNF-alpha activity in PAM cultures as early as 2 h after inoculation, as assessed by a colorimetric cytotoxicity assay. This activity could be blocked by rabbit anti-recombinant bovine TNF-alpha serum. In contrast, medium alone, polystyrene beads, and productive infection by OvLV did not induce TNF-alpha activity in PAM cultures. Bacterial pathogens which infect pulmonary macrophages may elicit the secretion of TNF-alpha within the lungs and lead to the cachectic state associated with chronic pneumonia.

Inflammatory responses to Pneumocystis carinii in mice selectively depleted of helper T lymphocytes

Pneumocystis carinii is the most important pulmonary pathogen in patients with the acquired immunodeficiency syndrome, but host defenses against P. carinii are not well characterized. We recently reported an experimental model of P. carinii infection, in which mice selectively depleted of CD4+ lymphocytes develop pulmonary infection after inoculation with P. carinii. In the current study, we compared lung inflammatory responses to P. carinii inoculation in CD4-depleted mice and in normal mice in order to further characterize host defenses against P. carinii. We hypothesized that depletion of CD4+ lymphocytes would prevent recruitment and activation of inflammatory cells in the lungs of these mice, allowing progressive infection with P. carinii. We found that CD4-depleted mice were unable to recruit CD4+ lymphocytes into their lungs and developed progressive infection with P. carinii, but mounted exuberant inflammatory responses to the organisms. These inflammatory responses were characterized by perivascular infiltration with mononuclear cells, increases in cell numbers in bronchoalveolar lavage (particularly CD8+ lymphocytes), and activation of alveolar macrophages (enhanced Ia antigen expression). In contrast, normal mice recruited CD4+ lymphocytes into their lungs and eliminated organisms with only minimal inflammatory responses. We conclude that depletion of CD4+ lymphocytes does not prevent the recruitment and activation of inflammatory cells in the lung. These inflammatory responses occur by mechanisms independent of CD4+ lymphocytes and are insufficient to provide effective host defense against P. carinii.