FEVER AND NEW LUNG INFILTRATES IN THE IMMUNOCOMPROMISED HOST

[The place of bronchoalveolar lavage in the diagnosis of pneumonia in the immunocompromised patient]

INTRODUCTION

Bronchoalveolar lavage (BAL) was previously considered as the standard diagnostic procedure to investigate pneumonia occurring in immunocompromised patients, and it is probably still widely used. However, the development of new microbiological diagnostic tools, applicable to samples obtained non-invasively, leads to questioning of the predominant place of BAL in this situation.

BACKGROUND

The available studies agree on the acceptable tolerance of BAL performed in immunocompromised patients. Although imperfect, the diagnostic yield of BAL in immunocompromised patients is well established, but it may vary between studies depending on the underlying disease. However, it must also be compared to the yield of non-invasive microbiological tools, now widely available and effective. The position of BAL remains important both for the diagnosis of fungal infections (invasive aspergillosis, pneumocystis pneumonia) and non-infectious lung diseases both of which occur frequently in immunocompromised patients.

CONCLUSION

The place of BAL in the diagnostic work-up of pneumonia occurring in immunocompromised patients must be considered in the framework of a structured consideration, taking into account the diagnostic performance of non invasive microbiological tests and the broad spectrum of lung diseases occurring in this context.

Contraindications and safety of transbronchial lung biopsy via flexible bronchoscopy. A survey of pulmonologists and review of the literature

BACKGROUND

Transbronchial lung biopsy (TBLB) via flexible bronchoscopy is a common procedure performed by pulmonologists. Limited scientific data exist concerning the risk of this procedure in patients with conditions that may adversely affect the rate of procedural complications.

OBJECTIVES

To evaluate the current practice pattern and attitude of pulmonologists toward the performance of TBLB in the presence of high-risk conditions.

METHODS

A survey was constructed and distributed at the American College of Chest Physicians annual meeting, held in Philadelphia, USA, in November of 2001.

RESULTS

A total of 227 surveys were distributed with a return of 158 (69.6%). Anticoagulation medications are temporarily held prior to TBLB by the majority of our survey respondents (98.7% for intravenous heparin, 90.5% for warfarin, and 87.3% for low-molecular-weight heparin). Medications with effect on platelet function are held by fewer pulmonologists. There is a wide variation in the pulmonologists' perception of the risk of performing TBLB when certain medical conditions coexist: pulmonary hypertension [absolute contraindication (AC), 28.7%; relative contraindication (RC) 58.6%], superior vena cava syndrome (AC 19.6%, RC 51%), mechanical ventilation (AC 17.8%, RC 58.6%) and lung cavity/abscess (AC 7%, RC 44.9%). A significant percentage of pulmonologists (55%) do not regard an elevated serum creatinine at any level as AC to TBLB. Thirty-eight percent of the survey participants administer desmopressin prior to TBLB in uremic patients to prevent excessive bleeding.

CONCLUSIONS

Prior to performing bronchoscopic TBLB, the majority of pulmonologists temporarily holds anticoagulation medications. However, there is a lack of agreement in relation to perceived contraindications and safety of TBLB.

The use of allopurinol in the inhibition of obliterative bronchiolitis of the transplanted lung

Long-term survival following lung transplantation has been limited primarily by the development in patients' lungs of a rejection-related obliteration of terminal bronchioles by fibroblasts. It is known to result from frequent and persistent acute lung rejection and its physiological features include a progressive decline in the lung function measurement of forced expiratory volume in 1 s. We report the dramatic effect on this hitherto usually fatal condition of a specific inhibition of purine metabolism at the xanthine oxidase enzyme by the hypoxanthine analogue allopurinol. The effect of this drug in heart-lung transplant patients with deteriorating lung function in reducing the rate of rejection and in stabilizing lung function was apparent over as short a follow-up period as 3 months and in ten patients. Although the follow-up time is short, we believe the effects are so striking as to require reporting although the mechanisms of this phenomenon are not yet well understood.

Role of bronchoscopy in modern medical intensive care unit

This article gives a broad overview of the increasingly important applications of bronchoscopy, flexible (FOB) and rigid (RB), in a modern medical intensive care unit. Special emphasis is made to bronchoscopy use in mechanically ventilated patients. Therapies such as endobronchial stenting and Nd:YAG laser are being used to improve respiratory failure and facilitate weaning from mechanical ventilation. Practical applications of recent advancements in technology (endobronchial stenting, laser therapy, and so forth), the increasing use of rigid bronchoscopy, and the new generation of flexible bronchoscopes like battery bronchoscopes, and ultra-thin bronchoscopes, are also discussed. The risks, potential benefits, complications, and suggested technique of performing bronchoscopy in mechanically ventilated patients are reviewed.

Chlamydia pneumoniae: a new opportunistic infectious agent in AIDS?

OBJECTIVE: To determine the incidence of Chlamydia pneumoniae respiratory tract infection in HIV-positive or AIDS patients. METHODS: Serum samples from 82 HIV-positive patients with fever and respiratory symptoms were evaluated using microimmunofluorescence assay to detect C. pneumoniae-specific IgG and IgM antibodies. RESULTS: Twenty patients were found to have IgG antibodies to C. pneumoniae at titers ranging between 1:16 and 1:1024. Seven of the patients had evidence of acute C. pneumoniae infection (a fourfold rise in the titer of IgG antibody, or a single IgG titer of greater-than-or-equal1:512, or a single IgM titer greater-than-or-equal1:16). Five were diagnosed as having pneumonia and two bronchitis. No co-infection with other respiratory tract pathogens was found. CONCLUSIONS: Results of this study indicate that C. pneumoniae may play a role in the etiology of respiratory tract infections in HIV-positive patients; this fact should affect empirical antibiotic prescription.

Pulmonary mucormycosis: results of medical and surgical therapy

Mucormycosis is an opportunistic fungal infection that commonly begins by invading the respiratory tract. The purpose of the present study was to define the clinical presentation of pulmonary mucormycosis and to evaluate current treatment regimens. Thirty patients treated at our institution and 225 cases reported in the literature were reviewed. For the combined groups, the mean age at presentation was 41 +/- 21 years and associated medical conditions included leukemia or lymphoma (37%), diabetes mellitus (32%), chronic renal failure (18%), history of organ transplantation (7.6%), or a known solid tumor (5.6%). The in-hospital mortality was 65% for patients with isolated pulmonary mucormycosis, 96% for those with disseminated disease, and 80% overall. The mortality in patients treated surgically was 11%, significantly lower than the 68% mortality in those treated medically (p = 0.0004). The most common causes of death were fungal sepsis (42%), respiratory insufficiency (27%), and hemoptysis (13%). Pulmonary mucormycosis has a high mortality; however, antifungal agents appear to improve survival. In addition, surgical resection may provide additional benefit to patients with pulmonary mucormycosis confined to one lung.

Mycoplasma pneumoniae as the causative agent for pneumonia in the immunocompromised host

A young man undergoing chemotherapy for Ewing's sarcoma presented with fever, neutropenia, anemia, thrombocytopenia, and a new infiltrate on the chest roentgenogram. Routine cultures and cytopathologic examination of bronchoalveolar lavage fluid provided no evidence for an etiology; however, special cultures of the BAL fluid demonstrated heavy growth of Mycoplasma pneumoniae. We recommend that evaluation of pneumonia in the immuno-compromised host include appropriate cultures of BAL fluid for M pneumoniae, particularly when the patient is 5 to 25 years old, the age of high incidence of mycoplasmal pneumonia.

Reversed helper/suppressor T-lymphocyte ratio in bronchoalveolar lavage fluid from patients with breast cancer and Pneumocystis carinii pneumonia

Pneumocystis pneumonia (PCP) usually occurs in patients with hematologic malignancies and acquired immunodeficiency syndrome (AIDS). Patients with solid tumors represent a very small fraction of the reported cases of PCP. Over an 18-month period, PCP was diagnosed in three patients who had received radiation and chemotherapy for breast cancer. In all three patients, there was no serologic or clinical evidence of AIDS. Direct staining of bronchoalveolar lavage fluid (BAL) revealed Pneumocystis carinii, and cellular analysis of BAL revealed an increased percentage of lymphocytes with reversed helper/inducer:suppressor/cytotoxic T-cell (CD4:CD8) ratio. Because decreased CD4:CD8 ratio in BAL is commonly accepted as findings consistent with hypersensitivity pneumonitis and AIDS, we conclude that similar findings in patients without AIDS are not specific for hypersensitivity pneumonitis, and P. carinii should be ruled out in the appropriate clinical setting.

The usefulness of open-lung biopsy in the pediatric bone marrow transplant population

From October 1976 to October 1986, 126 children had bone marrow transplants at the Children's Hospital of Philadelphia. The indications were acute lymphocytic leukemia (ALL) (30), nonlymphocytic leukemia (24), aplastic anemia (15), solid tumors (47), and miscellaneous conditions (10). Of these, 21 (17%) underwent 22 open-lung biopsies. Fourteen of these patients showed no causative microorganism. When a cause was found it was viral (usually cytomegalovirus [CMV]) in three, fungal in one, Pneumocystis carinii alone in two, both viral and pneumocystis in one, and a combination of viral, bacterial, and pneumocystis in one. Thirteen patients died due to continued deterioration after the biopsy. In only two patients was there a significant change in antimicrobial therapy as a result of the biopsy. Both had Pneumocystis (one in combination with virus and bacteria). One patient with chronic infiltrates showed a lymphocytic interstitial pneumonia, which responded well to steroids. Open-lung biopsy is currently of limited value in this patient population. Survival is dismal unless the patient has Pneumocystis. We believe that prospective studies should be set up to compare open-lung biopsy with empiric antimicrobial therapy. A major emphasis must be on prevention.

Modulation of rat bronchoalveolar lavage cell function by the intratracheal delivery of interferon-gamma

To determine if there is a rationale for compartmentalized immunostimulation, we have carried out a series of experiments to evaluate whether intratracheal delivery of interferon-gamma (rRatIFN-gamma) can activate rat bronchoalveolar lavage cells (BAL) for in vitro expression of tumoricidal activity against xenogeneic P815 tumor cells and enhanced in vitro microbicidal activity against the intracellular protozoan Toxoplasma gondii. Treatment of rat alveolar macrophages in vitro activates them for both of these activities as well as enhanced production of superoxide anion. We found that a single intratracheal dose of 5,000-10,000 units of rRatIFN-gamma activated rat BAL for both microbicidal and tumoricidal activity. To determine the duration of activation, microbicidal activity was determined 1, 2, 3, 5, and 7 days after a single intratracheal dose of 5,000 units of IFN. Enhanced microbicidal activity was maintained through day 3 but returned to control levels by day 5. Alveolar macrophages always accounted for the majority of cells in the lavage populations. However, intratracheal IFN caused an increase in the number of polymorphonuclear leukocytes and lymphocytes in the lavageable cells and, although these cells were always in the minority, they may have contributed to both the tumoricidal and microbicidal activity of the lavage cells. These studies demonstrate that local administration of an immunostimulant can activate pulmonary defense cells and may be a feasible route of drug delivery for prophylaxis against pulmonary infections.

Transbronchial biopsy during mechanical ventilation

The value and risk of transbronchial biopsy (TBB) was assessed in 15 cases requiring mechanical ventilation for progressive pulmonary infiltrates. TBB was diagnostic in five patients, and in two additional cases a diagnosis was made from the accompanying bronchial secretions. TBB results significantly altered the therapeutic management in seven cases. The alveolar-arterial gradient P(A-a)O2, widened by a mean of 110 mm Hg in nine patients; however, this change was transient and clinically insignificant. Three instances of reversible hypercapnia (mean of 15 mm Hg) occurred. Complications included self-limited bleeding in three cases and one tension pneumothorax. No fatalities were attributable to TBB. In these hemodynamically stable patients requiring mechanical ventilation for diffuse lung disease, TBB was performed safely and provided important data.

Severe RSV bronchiolitis in an immunocompromised child

A 9-year-old with immunodeficiency developed a severe, diffuse respiratory illness that necessitated mechanical ventilation. Open lung biopsy revealed Respiratory Syncytial Virus (RSV) as the sole pathogen. RSV detection should be included in the differential diagnosis of diffuse lung disease in an immunocompromised child.

Transbronchial biopsy in the thrombocytopenic patient

Twenty-five flexible fiberoptic bronchoscopic procedures with transbronchial lung biopsies were performed in 24 severely thrombocytopenic immunocompromised patients (mean platelet count of 30,000/cu mm, with a range of 7,000/cu mm to 60,000/cu mm) during the diagnostic evaluation of pulmonary infiltrates. Three patients had self-limited endobronchial bleeding. A single death was attributable to massive hemorrhage after transbronchial biopsy and brushing. Specific etiologic diagnoses were established by bronchoscopy in nine cases.

Pulmonary cell populations in the immunosuppressed patient. Bronchoalveolar lavage findings during episodes of pneumonitis

Bronchoalveolar lavage (BAL) cell populations were determined in 47 immunosuppressed patients during episodes of pulmonary disease. Thirty six patients had AIDS and 11 had conventional causes of immunosuppression. Pulmonary disease was due to a variety of infectious and noninfectious causes and was similar in both groups. In the AIDS patients, the mean BAL cell proportions were 64.2 +/- 3.7 percent alveolar macrophages (MACS), 28.7 +/- 3.4 percent lymphocytes, 3.5 +/- 1.8 percent polymorphonuclear cells (PMN) and 1.6 +/- 0.6 percent eosinophils (EOS). The non-AIDS group had similar findings in the BAL, with 59.3 +/- 8.3 percent MACS, 34.8 +/- 7.2 percent lymphocytes, 5.5 +/- 1.7 percent PMN and 0.4 +/- 0.2 percent EOS. The most striking finding in each group was a significant increase in both the proportion and absolute number of lymphocytes compared to controls. This was in marked contrast to the peripheral blood findings of lymphopenia. There was no characteristic cell profile diagnostic of any specific pulmonary disease. There was also no direct relationship of the cells present to respiratory symptoms, roentgenographic abnormalities or survival from pulmonary disease. This study demonstrates that although there was wide individual variation in lavage findings, a local pulmonary inflammatory reaction consisting predominantly of lymphocytes occurs in the immunosuppressed host during episodes of lung disease. The significance of this lymphocyte alveolitis and the complex host pathogen interaction responsible for determining the cell populations present in the lungs of these patients requires further study.

Discriminant scorecard for diagnosis of invasive pulmonary aspergillosis in patients with acute leukemia

Invasive pulmonary aspergillosis, a serious opportunistic infection in adult patients with acute leukemia, is difficult to diagnose antemortem. To identify patients with invasive pulmonary aspergillosis without reliance on invasive diagnostic procedures, a discriminant scorecard for invasive pulmonary aspergillosis based on clinical parameters was evaluated in a three-phase study. In phase I, the records of 62 patients, including 15 with invasive pulmonary aspergillosis, were reviewed. Eleven clinical parameters distinguished patients with invasive pulmonary aspergillosis from control subjects. These parameters were combined into a discriminant scorecard. In phase II, the discriminant scorecard was validated by a blinded, retrospective review of 94 consecutive admissions. The discriminant scorecard score was highly associated with the clinical outcome (p less than 0.0005). The sensitivity of the discriminant scorecard was calculated as a range from 62.9 to 92.8 percent and the specificity as a range from 87.5 to 98.3 percent. In phase III, the clinical utility of the discriminant scorecard was determined by its prospective application to 49 consecutive patient admissions. The discriminant scorecard identified patients with invasive pulmonary aspergillosis at an average of 4.1 days prior to clinical recognition of the disease and initiation of amphotericin B therapy. The discriminant scorecard outperformed a complex function based on multiple linear regressions, was easy to use, and did not require difficult calculations. Thus, for this patient population, the discriminant scorecard was an accurate, useful noninvasive screening test for invasive pulmonary aspergillosis. The scorecard allows more rapid clinical identification of patients with this infection and could lead to improved patient survival through earlier diagnostic and therapeutic intervention.

Spectrum of pulmonary diseases associated with the acquired immune deficiency syndrome

Over a four-year period, 130 patients with the acquired immune deficiency syndrome were studied to assess the incidence and spectrum of pulmonary disease associated with this illness. In 61 patients (47 percent), respiratory abnormalities were either present on admission or later developed. Multiple pathologic processes were present simultaneously in 24 patients and serial pulmonary problems developed in seven patients. Infection was the most common cause of pulmonary parenchymal disease and was due to Pneumocystis carinii (35 patients), cytomegalovirus (21 patients), Mycobacterium avium-intracellulare (13 patients), and bacteria (four patients). Noninfectious causes of parenchymal lung diseases were also frequently seen and included Kaposi's sarcoma (eight patients), non-specific pneumonitis (seven patients), and adult respiratory distress syndrome (four patients). Significant pleural disease was present in six cases and was usually related to Kaposi's sarcoma. A bronchospastic disorder developed in four patients. Pulmonary function tests, in particular the diffusing capacity and the difference between rest and exercise alveolar-arterial oxygen tension, were helpful in screening for pulmonary diseases. Patterns of clinical features and radiographic abnormalities were recognized and suggested specific diagnoses. Overall mortality from respiratory causes identified during the study was 41 percent, but varied markedly with the etiologic agent. Respiratory failure, however, carried a 100 percent mortality despite the underlying cause.

Role of fiberoptic bronchoscopy in the diagnosis of invasive pulmonary aspergillosis in patients with acute leukemia

The utility and safety of fiberoptic bronchoscopy in the diagnosis of invasive pulmonary aspergillosis in patients with acute leukemia have not been examined. The results of 21 bronchoscopic procedures in 19 patients with invasive pulmonary aspergillosis and acute leukemia were reviewed. Analysis was confined to the 16 patients who had histopathologically documented infection on biopsy or at autopsy. Fiberoptic bronchoscopy established or suggested the diagnosis of invasive pulmonary aspergillosis in eight of 16 (50 percent) patients. Transbronchial or bronchial biopsy added only one diagnosis to those obtained by bronchial washing and brushing. Although fiberoptic bronchoscopy was a safe and well-tolerated procedure in our patients with invasive pulmonary aspergillosis and acute leukemia, its success rate was only 50 percent overall, and it appeared to be even less successful when performed early in the course of the disease. Fiberoptic bronchoscopy is a useful first procedure for the evaluation of patients with acute leukemia and possible invasive pulmonary aspergillosis, but a negative result does not exclude aspergillosis. Further diagnostic procedures, including repeated bronchoscopy, or institution of empiric antifungal therapy may be warranted if the clinical suspicion of invasive pulmonary aspergillosis is high.

Pulmonary infiltrates in immunocompromised patients: diagnosis by cytological examination of bronchoalveolar lavage fluid

Thirty pulmonary infiltrates in 26 patients were investigated by bronchoalveolar lavage. Sixteen of the patients were on therapeutic immunosuppression for renal disease or transplant and 10 had leukaemia, lymphoma, or allied conditions. A rapid specific diagnosis was made in 21 (70%) episodes by cytological examination of the fluid and in 28 (93%) by a combination of cytology and microbiology. No complications from haemorrhage or pneumothorax ensued. Pneumonia due to Pneumocystis carinii was the most common diagnosis (27%), but opportunistic infections from cytomegalovirus, candida, aspergillus, zygomycetes, and acid fast bacilli were also identified by cytology. Two episodes were caused by occult pulmonary haemorrhage and five patients had malignant infiltration of the lung from leukaemia, myeloma, Hodgkin's disease, and lymphoplasmacytoid lymphoma. In two of these there was also evidence of infection. In seven cases with non-diagnostic cytology infections due to Staphylococcus aureus, Pseudomonas aeruginosa, pneumococcus, micrococcus, and Aspergillus fumigatus were identified on culture. In two patients (7%) no specific diagnosis was established by lavage: one had serological evidence of legionella infection and the second had P aeruginosa septicaemia. Twelve (75%) of the renal patients and six (60%) of those with leukaemia, lymphoma, and allied conditions recovered.

Pneumonia associated with rising cytomegalovirus antibody titres in a healthy adult

Images

Nosocomial infections

Recent developments in the understanding of nosocomial infection in general and nosocomial respiratory infections in particular are elucidated. Although the discussion focuses on aerobic bacteria, data are presented to indicate the growing realization that unusual and newly discovered microorganisms play a significant role in hospital-acquired infections. Strategies for the control or prevention of nosocomial infections are highlighted.

Precedents for meaningful recovery during treatment in a medical intensive care unit. Outcome in patients with hematologic malignancy

The medical records of 77 patients with hematologic malignancy who were admitted to a medical intensive care unit over a 21-month period were reviewed. The overall hospital mortality rate was 80 percent. Sixteen patients (21 percent) were discharged from the intensive care unit but eventually died in the hospital. The cause of death was the result of a new problem in only three of these 16 patients. Hypotension (shock) and acute respiratory failure were the reasons prompting admission to the intensive care unit in 75 percent, but death in the intensive care unit was almost always the result of intractable hypotension rather than refractory hypoxemia. Only four of 52 patients who required mechanical ventilation left the hospital. In all four, the duration of ventilatory support was less than five days and the cause of respiratory failure was noninfectious in nature. Factors such as congestive heart failure, leukopenia, and abnormalities in mental status modified the hospital course, but did not alter outcome once prolonged mechanical ventilation became necessary. The data suggest that once acute respiratory failure develops in patients with lymphoma or leukemia, presumably as a result of infection, and mechanical ventilation for more than a relatively brief period is required, the prognosis is uniformly grim. Decisions to limit aggressive therapies is subsets of intensive care patients such as these should be aided by data that show a lack of precedent for meaningful recovery.

Pneumocystis carinii pneumonia and mucosal candidiasis in a previously healthy homosexual man

A fatal case of Pneumocystis carinii pneumonia in a previously healthy homosexual man with no evidence of malignancy is reported. Despite appropriate treatment with high doses of i.v. trimethoprim-sulfamethoxazole, the patient died.

Pathologic features of the lung in the immunocompromised host

Acute pulmonary disease is a major complication of immunodeficiency, and it has become increasingly important with the expanded use of immunosuppressive drugs. When routine clinical evaluation fails to identify a specific etiologic agent, a morphologic diagnosis is pursued by means of one or more invasive procedures. Interpretation of the material obtained by these procedures poses a challenge to pathologists. In this paper, the important histopathologic patterns of pulmonary disease likely to be encountered in this setting are reviewed, with emphasis on differential diagnosis. In addition, various diagnostic techniques are discussed and compared, with regard to interpretation of findings and diagnostic yields.