The relationship between cytomegalovirus retrieved by bronchoalveolar lavage and mortality in patients with HIV

Epidemiology and clinical impact of respiratory co-infections at diagnosis of Pneumocystis jirovecii Pneumonia

OBJECTIVES

To describe the epidemiology and clinical impact of respiratory co-infections at diagnosis of Pneumocystis jirovecii Pneumonia (PcP).

METHODS

A retrospective observational study was conducted between January 2011 and April 2019 to evaluate respiratory co-infections at diagnosis of PcP patients, in two tertiary care hospitals. Respiratory co-infection was defined by the identification of pathogens from P. jirovecii-positive samples.

RESULTS

Of the 7 882 respiratory samples tested for P. jirovecii during the 8-year study period, 328 patients with final diagnosis of PcP were included in this study. Mean age was 56.7 ± 14.9 years, 193 (58.8%) were male, 74 (22.6%) had a positive HIV serology, 125 (38.1%) had a viral co-infections, 76 (23.2%) a bacterial co-infections and 90-day mortality was 25.3%. In overall population, 90-Day mortality was independently associated with a solid tumor underlying disease (OR 11.8, 1.90-78, p=0.008), SOFA score at admission (OR 1.62, 1.34-2.05; p<0.001) and CMV respiratory co-infection (OR 3.44, 1.24-2.90; p=0.02). Among HIV-negative patients, respiratory CMV co-infection was associated with a worse prognosis, especially when treated with adjunctive corticosteroid therapy.

CONCLUSIONS

Respiratory CMV co-infection at diagnosis of PcP was independently associated with increased 90-day mortality, specifically in HIV-negative patients.

Pulmonary coinfection by Pneumocystis jirovecii and Cryptococcus species in a patient with undiagnosed advanced HIV

Pneumocystis jirovecii is a common cause of pneumonia in patients with advanced HIV. In a lot of cases, there is a concomitant pulmonary infection. Cryptococcosis presents as a common complication for people with advanced HIV. However, it usually presents as meningitis rather than pneumonia. We present a case of a patient with coinfection by P. jirovecii and Cryptococcus spp without neurological involvement and a single nodular pulmonary lesion.

A rare case of CMV pneumonia in HIV-infection

Cytomegalovirus (CMV) pneumonia is a rare opportunistic infection in the setting of HIV (Human Immunodeficiency Virus)-infection. Establishing accurate diagnosis of CMV pneumonia in HIV-infection can be challenging. Co-infections by multiple opportunistic pathogens are common and a high degree of clinical vigilance to evaluate for multiple infections, including CMV pneumonia, should be maintained. As there can be a degree of overlap in clinical and radiological features amongst different opportunistic infections affecting the lungs, definitive microbiological and cytohistologic evidences are needed. Reliance on microbiological evidence of CMV in respiratory specimens alone for the diagnosis of CMV pneumonia will lead to an over-diagnosis of the condition and unnecessary treatment.

In our case report, we describe a 53-year-old man with recently diagnosed HIV-infection who presented with non-resolving pneumonia. A diagnosis of CMV pneumonia was reached through consistent clinical, radiological, microbiological and cytologic investigations. The patient made a full clinical recovery after being started on anti-CMV treatment.

The impact of concomitant pulmonary infection on immune dysregulation in Pneumocystis jirovecii pneumonia

Background

Concurrent infection may be found in Pneumocystis jirovecii pneumonia (PJP) of non-acquired immunodeficiency syndrome (AIDS) patients, however, its impact on immune dysregulation of PJP in non-AIDS patients remains unknown.

Methods

We measured pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-17, monocyte chemoattractant protein-1 (MCP-1) and anti-inflammatory cytokines including IL-10 and transforming growth factor (TGF)-β1 and IL-1 receptor antagonist (IL-1RA) and inflammatory markers including high mobility group box 1, Krebs von den Lungen-6, receptor for advanced glycation end product, advanced glycation end product, surfactant protein D in bronchoalveolar lavage fluid (BALF) and blood in 47 pure PcP and 18 mixed PJP and other pulmonary infections (mixed PJP) in non-AIDS immunocompromised patients and explored their clinical relevance. The burden of Pneumocystis jirovecii in the lung was determined by counting number of clusters of Pneumocystis jirovecii per slide and the concentration of β-D-glucan in BALF. PJP severity was determined by arterial oxygen tension/fraction of inspired oxygen concentration ratio, the need of mechanical ventilation and death.

Results

Compared with pure PJP group, mixed PJP group had significantly higher BALF levels of IL-1β, TNF-α and IL-8 and significantly higher blood levels of IL-8. The BALF ratios of TNF-α/IL-10, IL-8/IL-10, IL-1β/IL-10, TNF-α/TGF-β1, IL-8/TGF-β1, IL-1β/TGF-β1 and IL-1β/IL-1RA were significantly higher in mixed than in pure PJP patients. There was no significant difference in clinical features and outcome between pure and mixed PJP groups, including inflammatory biomarkers and the fungal burden. In pure PJP patients, significantly higher BALF levels of IL-8 and the ratios of IL-8/IL-10, IL-1β/TGF-β1, MCP-1/TGF-β1, MCP-1/IL1RA and IL-8/TGF-β1 were found in the patients requiring mechanical ventilation and in non-survivors.

Conclusions

In summary, concurrent pulmonary infection might enhance immune dysregulation of PJP in non-AIDS immunocompromised patients, but did not affect the outcome as evidenced by morbidity and mortality. Because of limited number of cases studied, further studies with larger populations are needed to verify these issues.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2466-14-182) contains supplementary material, which is available to authorized users.

Clinical review: Respiratory failure in HIV-infected patients--a changing picture

Respiratory failure in HIV-infected patients is a relatively common presentation to ICU. The debate on ICU treatment of HIV-infected patients goes on despite an overall decline in mortality amongst these patients since the AIDS epidemic. Many intensive care physicians feel that ICU treatment of critically ill HIV patients is likely to be futile. This is mainly due to the unfavourable outcome of HIV patients with Pneumocystis jirovecii pneumonia who need mechanical ventilation. However, the changing spectrum of respiratory illness in HIV-infected patients and improved outcome from critical illness remain under-recognised. Also, the awareness of certain factors that can affect their outcome remains low. As there are important ethical and practical implications for intensive care clinicians while making decisions to provide ICU support to HIV-infected patients, a review of literature was undertaken. It is notable that the respiratory illnesses that are not directly related to underlying HIV disease are now commonly encountered in the highly active antiretroviral therapy (HAART) era. The overall incidence of P. jirovecii as a cause of respiratory failure has declined since the AIDS epidemic and sepsis including bacterial pneumonia has emerged as a frequent cause of hospital and ICU admission amongst HIV patients. The improved overall outcome of HIV patients needing ICU admission is related to advancement in general ICU care, including adoption of improved ventilation strategies. An awareness of respiratory illnesses in HIV-infected patients along with an appropriate diagnostic and treatment strategy may obviate the need for invasive ventilation and improve outcome further. HIV-infected patients presenting with respiratory failure will benefit from early admission to critical care for treatment and support. There is evidence to suggest that continuing or starting HAART in critically ill HIV patients is beneficial and hence should be considered after multidisciplinary discussion. As a very high percentage (up to 40%) of HIV patients are not known to be HIV infected at the time of ICU admission, the clinicians should keep a low threshold for requesting HIV testing for patients with recurrent pneumonia.

Other HIV-associated pneumonias

The incidence, mortality, and epidemiology of human immunodeficiency virus (HIV)-associated pulmonary infections have changed as a result of effective antiretroviral and prophylaxis antimicrobial therapy. The clinical presentation, radiographic abnormalities, and treatment of pneumonia from various uncommon pathogens in patients with AIDS can be different from those in immunocompetent patients. Advances in invasive and noninvasive testing and molecular biological techniques have improved the diagnosis and prognosis of pulmonary infections in patients infected with HIV. This review focuses on pulmonary infections from nontuberculosis mycobacteria, cytomegalovirus, fungi (aspergillosis, cryptococcosis, endemic fungi), and parasites (toxoplasmosis), and uncommon bacterial pneumonia (nocardiosis, rhodococcosis) in these patients.

Outcomes of non-HIV-infected patients with Pneumocystis pneumonia and concomitant pulmonary cytomegalovirus infection

BACKGROUND

The pathogenic effect of concomitant pulmonary cytomegalovirus (CMV) infection on morbidity and mortality of Pneumocystis jirovecii pneumonia (PCP) has been questioned in the case of non-HIV-infected patients.

METHODS

We conducted a retrospective cross-sectional study of patients who were diagnosed with PCP by bronchoalveolar lavage. We compared demographics, clinical characteristics, morbidity, and mortality in non-HIV-infected PCP patients with (n = 31) and without (n = 75) pulmonary CMV infection. Morbidity was assessed by length of hospital stay, admission to the intensive care unit, and use of mechanical ventilation. Mortality was defined as 30-day and 90-day all-cause mortality.

RESULTS

Morbidity and mortality did not differ between PCP patients with and without pulmonary CMV infection. In multivariate analysis using the Cox proportional hazard model, haematological malignancy (relative risk (RR) 0.20, 95% confidence interval (95% CI) 0.06-0.71), PCP treatment duration (RR 0.81, 95% CI 0.75-0.88), changing to a second-line regimen due to treatment failure (RR 4.51, 95% CI 1.61-12.64), and mechanical ventilation (RR 17.99, 95% CI 4.83-67.04) were independently associated with 30-day all-cause mortality. Being a solid organ transplant recipient (RR 0.17, 95% CI 0.05-0.56) and the use of mechanical ventilation (RR 6.49, 95% CI 2.84-14.83) were independently associated with 90-day all-cause mortality. However, concomitant pulmonary CMV infection was not associated with either 30-day or 90-day mortality.

CONCLUSIONS

Our results suggest that concomitant pulmonary CMV infection does not significantly affect the prognosis of PCP, as indicated by morbidity and mortality in non-HIV-infected patients with PCP. Based on this result, we propose that it is not essential to administer an anti-CMV regimen when CMV is co-isolated from the bronchoalveolar lavage in patients with PCP.

Systematic review on the etiology and antibiotic treatment of pneumonia in human immunodeficiency virus-infected children

BACKGROUND

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected children.

OBJECTIVES AND METHODS

A systematic review of studies that were published between January 1990 and February 2009 on the etiology and antimicrobial or adjunctive systemic management of CAP in HIV-infected children.

RESULTS

Pneumocystis jirovecii had the strongest association with HIV infection, with a summary odds ratio of 10.1 (95% confidence interval [CI], 17.7-62.1) and 9.1 (95% CI, 2.5-33.1) in antemortem and postmortem studies, respectively. Cytomegalovirus was strongly associated with HIV positivity among fatal cases of pneumonia (summary odds ratio = 14.4 [95% CI, 6.7-30.8]). There was a trend toward a greater prevalence of Staphylococcus aureus (odds ratio, 2.5; 95% CI, 0.95-6.4) in HIV-infected children. Major limitations identified included substantial methodological heterogeneity across studies, limited sensitivity of assays for diagnosing bacterial pneumonia, and studies primarily being undertaken in the absence of antiretroviral treatment or cotrimoxazole prophylaxis. No a priori-planned randomized controlled trials on antimicrobial management of CAP in HIV-infected children were identified.

CONCLUSIONS

A World Health Organization panel used this review as well as analysis of risks and benefits to revise recommendations for antimicrobial treatment of CAP. Ampicillin plus gentamicin or ceftriaxone is now recommended as first-line empiric regimens for treating severe and very severe CAP in HIV-infected children. In addition, treatment with cloxacillin or vancomycin is recommended in settings with a high incidence of methicillin-resistant S. aureus, and particularly if clinical or microbiological evidence of S. aureus pneumonia exist. Further studies in HIV-infected children on CAP etiology and antibiotic treatment are required in the era of antiretroviral treatment.

Pulmonary infections in the HIV-infected patient in the era of highly active antiretroviral therapy: an update

The highly active antiretroviral therapy (HAART) era began in 1996 when the combination of multiple antiretroviral agents was found to improve outcomes in HIV-infected patients. HAART has made a tremendous impact on the progression of HIV and on the morbidity and mortality associated with its opportunistic infections. HIV-positive patients who respond to HAART have a decreased incidence of opportunistic infections. Studies have documented close to a 50% decline in the incidence of pneumocystis pneumonia and bacterial pneumonia with the use of antiretroviral therapy. Primary and secondary prophylaxis for pneumocystis pneumonia can be discontinued in patients who show a sustained response to antiretroviral therapy. Unique to the HAART era, immune reconstitution syndrome is characterized by a paradoxical deterioration of a preexisting infection that is temporally related to the recovery of the immune system. Recently, more and more patients are being admitted for non-AIDS related illnesses in the HAART era.

Role of bronchoalveolar lavage in interstitial lung disease

Bronchoalveolar lavage remains an important research tool in understanding ILD. It is still an important part of the clinical management of patients with ILD. It is most useful in detecting unusual forms of ILD. It helps the clinician narrow down the possible causes of the interstitial pattern. It also can confirm a clinical impression of certain conditions. Although rarely diagnostic, it is often supportive. In conjunction with high-resolution CT scan, most patients with ILD can be diagnosed using relatively noninvasive methods.

Pulmonary cytomegalovirus infection in immunocompromised patients

BACKGROUND

Cytomegalovirus (CMV) infection and CMV disease are frequent complications in immunocompromised patients. In this study, the incidence of pulmonary CMV infection was analyzed in different groups of immunocompromised patients and the diagnostic value of immunostaining with anti-CMV antibodies in BAL cells was evaluated in regard to the diagnosis of CMV pneumonitis.

METHODS

Five hundred eighty consecutive BAL procedures were analyzed prospectively in 442 immunocompromised and 126 nonimmunocompromised control subjects. CMV culture in BAL fluid was performed by shell vial assay and immunostaining using three monoclonal anti-CMV antibodies.

RESULTS

The incidence of culture results positive for CMV in the BAL fluid varied from 20 to 30% in HIV-positive patients, in patients following stem cell or renal transplantation, and in patients with autoimmune disease or lung fibrosis treated with immunosuppressive agents. CMV was cultured from 4.4% of BALs in patients treated with high-dose chemotherapy and from 2.4% of control subjects. CMV disease developed in 37 patients; in 18 of these patients, CMV pneumonitis was present. The results of CMV immunostaining were positive in a total of 22 BALs, all in patients with CMV disease. The sensitivity, specificity, and positive and negative predictive values of positive CMV immunostaining results for the diagnosis of CMV pneumonitis were 88.9%, 98.6%, 72.7%, and 99.5%, respectively.

CONCLUSION

The incidence of pulmonary CMV infection is similar in different groups of immunocompromised patients except for patients following high-dose chemotherapy. CMV immunostaining in the BAL fluid is a very helpful method to diagnose CMV pneumonitis in these patients.

Prognostic markers of short-term mortality in AIDS-associated Pneumocystis carinii pneumonia

BACKGROUND

Since 1990, corticosteroids have been recommended as adjunctive therapy for patients with AIDS-associated Pneumocystis carinii pneumonia (PCP) and respiratory failure. We hypothesized that the natural course of AIDS-associated PCP has changed in the era of adjunctive corticosteroid therapy.

OBJECTIVE

To study variables obtained on hospital admission for possible prognostic value of short-term (3-month) outcome of PCP.

DESIGN AND PATIENTS

Prospective observational study of 176 consecutive HIV-1-infected individuals with PCP between 1990 and 1999.

METHOD

Cox proportional-hazards regression models.

RESULTS

Univariate analysis showed that age, one or more prior episodes of PCP, use of antimicrobial therapy other than trimethoprim-sulfamethoxazole (TMP-SMZ), use of PCP prophylaxis at diagnosis, and culture of cytomegalovirus (CMV) in BAL predicted progression to death within 3 months. After adjustment, age (relative risk [RR], 4.1; 95% confidence interval [CI], 1.8 to 9.3), initial antimicrobial therapy other than TMP-SMZ (RR, 3.1; 95% CI, 1.2 to 8.5), use of PCP prophylaxis (RR, 5.6; 95% CI, 2.2 to 14.4), and culture of CMV in BAL fluid (RR, 2.7; 95% CI, 1.3 to 5.6) remained independent predictors of a poor outcome. In contrast, neither PO(2) nor serum lactate dehydrogenase, which in earlier studies were identified as prognostic markers, were predictors of mortality.

CONCLUSION

Age, initial anti-PCP therapy, use of PCP prophylaxis, and BAL CMV status may be useful predictors of outcome of PCP in patients treated in the era of adjunctive corticosteroid therapy.

Pneumocystis carinii pneumonia requiring intensive care management: survival and prognostic study in 110 patients with human immunodeficiency virus

OBJECTIVE

To perform a descriptive study of patients with acute respiratory failure secondary to acquired immunodeficiency syndrome-related Pneumocystis carinii pneumonia and to identify variables that are predictive of death within 3 months.

DESIGN

Case series study.

SETTING

Infectious disease intensive care unit (ICU) in a university hospital.

PATIENTS

Detailed clinical, laboratory, and ventilatory data were collected prospectively within 48 hrs of admission and during the ICU stay in 110 consecutive human immunodeficiency virus-infected patients requiring ICU management with or without mechanical ventilation for P. carinii pneumonia-related acute respiratory failure.

MEASUREMENTS AND MAIN RESULTS

Continuous positive airway pressure was used initially in 66 (60%) patients. Among the 34 patients (31%) who required mechanical ventilation, including 12 at admission and 22 after failure of continuous positive airway pressure, 76% died. The 3-month mortality rate after ICU admission was estimated at 34.6% (95% confidence interval [CI], 25%-44%). The 1-yr survival rate was estimated at 47% (95% CI, 36%-58%). With successive multiple logistic regression models analyzing the relative prognostic importance of baseline clinical and laboratory tests variables, ventilation variables, and events in the ICU, only delayed mechanical ventilation after 3 days (odd ratio [OR], 6.7; 95% CI, 1.9-23.9), duration of mechanical ventilation of > or = 5 days (OR, 2.8; 95% CI, 1.1-6.9), nosocomial infection (OR, 5.2; 95% CI, 2.1-12.9), and pneumothorax (OR, 5; 95% CI, 1.7-14.7) were predictive of death within 3 months of ICU admission. Among patients with delayed mechanical ventilation on day 3 or later and with a pneumothorax associated or not associated with a nosocomial infection, the predicted probability of 3-month death was close to 100%.

CONCLUSIONS

Our data suggest that the most significant predictive factors of death were identifiable during the course of P. carinii pneumonia-related acute respiratory failure rather than at admission and can help in bedside decisions to withdraw intensive care support in such patients.

Diagnosis of lower respiratory tract infections: what we have and what would be nice

STUDY OBJECTIVES

To review the various methods used to diagnose lower respiratory tract infections.

DESIGN

Review of literature with appropriate references to various techniques proposed to diagnose pneumonia.

INTERVENTION

Compare and contrast different proposed approaches to diagnose pneumonia.

RESULTS

Bronchoscopic techniques appear more clear cut for certain nonbacterial pathogens. Their role in immunocompromised patients is more clear cut, while in the nonimmunocompromised patient, invasive diagnostic techniques probably provide a higher certainty of the final diagnosis of the patient. Recent interest has focused on nonbronchoscopic techniques for the mechanically ventilated patient. None of these techniques has been demonstrated to change clinical outcome.

CONCLUSIONS

Diagnosis of lower respiratory tract infection has to be tailored for the individual patient. Decision about which procedure to do is influenced by the patient's underlying immune status, level of illness, and response to empiric therapy.

Role of bronchoalveolar lavage in predicting survival of patients with human immunodeficiency virus infection

In this multicenter study, we investigated the prognostic factors that influence the risk of death in patients with human immunodeficiency virus (HIV) infection. Clinical and laboratory indices obtained from 161 HIV-seropositive patients who underwent a detailed morphologic and immunophenotypic evaluation of bronchoalveolar lavage (BAL) and peripheral blood cell populations were retrospectively analyzed. In 155 patients, death occurred within the 48-mo follow-up (mean follow-up: 14.8 mo; range: 1 to 48 mo). In the univariate analysis, the patient's age (> 30 yr), HIV disease status, HIV transmission category, number of opportunistic pathogens isolated from the BAL, percentage of BAL neutrophils, and low number of BAL CD4 T cells were predictive of increased mortality. In contrast, the presence of an alveolitis or an increase in the numbers of alveolar macrophages and CD3 T cells was associated with a decreased mortality. In the multivariate analysis, significant independent predictors were age, risk factor for HIV, and presence of an alveolitis. Furthermore, patients with a low number of BAL CD4 T cells had a particularly poor prognosis while the CD4 T-cell count in the peripheral blood (< 50 cells/mm3 in the majority of our patients) had a negligible effect on predicting survival. Our findings suggest the clinical utility of BAL analysis in patients infected with HIV.

Cytomegalovirus as a primary pulmonary pathogen in AIDS

In patients with AIDS, isolation of cytomegalovirus (CMV) from respiratory secretions is common. It is often found with other pathogens, which has led to debate regarding its role as a primary pulmonary pathogen. A retrospective investigation of patients with AIDS and CMV as a sole pulmonary isolate was performed in an attempt to describe their clinical presentation and course. All patients admitted to the hospital with pneumonia and with BAL or transbronchial biopsy (TBB) specimen positive for CMV between 1991 and 1994 were identified through a review of inpatient records. Inclusion criteria included positive CMV cultures from BAL, cytomegalic inclusion bodies from BAL or TBB, and thorough documentation of the absence of other pulmonary pathogens. Nine patients met the inclusion criteria for CMV pneumonitis. Seven were male and two were female, ages 26 to 44 years, and all had a history of opportunistic infections. Typical clinical presentation was characterized by increased respiratory rate, hypoxemia, and diffuse interstitial infiltrates. The mean CD4 count was 29.6 (+/- 22) cells per cubic millimeter, mean lactate dehydrogenase level was 414 (+/- 301) IU/L, and in seven patients in whom CMV antigen was measured it was greater than 50 positive cells per 200,000 WBCs. Three untreated patients died of respiratory failure and three had autopsy confirmation of CMV pneumonia. Five patients were treated with anti-CMV therapy for at least 2 weeks, and all demonstrated improvement in symptoms, oxygen saturation, and chest radiograph. At 3 months follow-up, all five patients were asymptomatic with no pulmonary symptoms. At 6 months follow-up, three of the five patients remained asymptomatic; the other two died of other opportunistic infections. In at least these nine patients, CMV represented a primary pulmonary pathogen. Patients who were treated responded quickly and were able to be discharged home from the hospital with marked improvement in their symptoms. We recommend that clinicians consider this diagnosis in the proper setting and consider treatment with anti-CMV therapy.

Approach to the patient with pulmonary disease

The approach to the HIV-infected patient with pulmonary disease is summarized by the algorithms in Figures 3 and 4. These are not intended to be followed in a rigid step-wise fashion. Rather, the practitioner's knowledge of the patient with his or her accompanying medical risks influences the path taken, including the depth and the speed of the evaluation. For example, the patient with cough who is afebrile and breathing at 18 breaths a minute, with a normal chest radiograph and a CD4 count of 350 cells/mm3, is reasonably treated with a macrolide or cephalosporin for bacterial bronchitis and clinical follow-up while awaiting cultures (see Fig. 4). A febrile patient with a cough productive of thin mucus, but known to have a CD4 count of 60 cells/mm3 should be started on anti-PCP therapy while being evaluated for PCP with an induced sputum and if nondiagnostic, a bronchoscope despite a normal chest radiograph. Screening can be as simple as placing an oximeter on the patient's finger in the clinic. If the oxygen saturation of a patient with a normal chest radiograph is low, then the patient should be hospitalized and begun on treatment for PCP while diagnostic evaluation is initiated. If the oxygen saturation is normal, the patient can be exercised to elicit desaturation. If there is no desaturation, PCP is unlikely. If the results are equivocal (i.e., a decrease in saturation, but less than 3%), rest and exercise arterial blood gases can be performed, along with a Dlco-Gallium scanning can be done in patients known to have abnormal Dlco or those who cannot exercise. Patients with focal infiltrates who have acute onset of symptoms (see Fig. 4) commonly have bacterial infections, but the possibility of PCP or TB should not be dismissed. Induced sputum should be examined if TB or PCP is suspected. Patients who are severely ill might go quickly to bronchoscopy without awaiting improvement on empiric therapy. The patient with diffuse infiltrates (see Fig. 4) needs no screening because the presence of disease is apparent from the radiograph. The diagnostic part quickly leads to bronchoscopy for these patients and the initiation of therapy for PCP when suspected. In patients with known pulmonary KS, gallium scanning can be helpful to rule out acute infection, but bronchoscopy is warranted if the patient is severely ill, or at high risk for PCP. This approach should avoid unnecessary procedures in patients with simple bacterial infections, without missing opportunistic infections and tumors.

Viruses and other miscellaneous organisms

Pulmonary infections caused by several types of viruses and other miscellaneous organisms may cause disease in HIV infection. Evidence suggests that pulmonary conditions may result from infections of the lung by HIV itself. Other viruses, most commonly cytomegalovirus, may be primary perpetrators of pneumonitis or may contribute to diseases caused by coexisting infections. Although diagnosis and assessment of the clinical significance of these infections may be difficult, their recognition is of practical importance because potentially effective therapeutic agents are available for several of them. Miscellaneous infections such as pulmonary toxoplasmosis and pertussis are other uncommon but potentially treatable complications of HIV disease.

Pulmonary disease

This article has presented the reader with an overview of the pulmonary disorders that develop during the course of HIV disease with special emphasis on the more commonly encountered entities. This information is intended to prepare the clinician to recognize the hallmark characteristics of the various diseases as well as atypical features. Despite the advances in basic understanding of the clinicopathologic consequences of infection with HIV, a cure has not been realized. There has, however, been success in controlling some of the major pulmonary problems that adversely affect both the quality and the length of life for persons with AIDS. For most complications of HIV infection, prognosis ultimately depends not only on treatment of the specific problem, but also controlling the relentless process of progressive immunosuppression. Continued research into treatment or prevention of HIV infection itself is needed, but at present prevention, rapid diagnosis, and treatment of recognized problems remain an intermediary goal.