Utility of bronchoalveolar lavage in assessing pneumonia in immunosuppressed renal transplant recipients

The cytological diagnosis of Pneumocystis jiroveci pneumonia in bronchoalveolar lavage

Objectives

Immunosuppressed individuals are more prone for opportunistic infections. Pneumocystis jiroveci pneumonia (PJP), previously known as Pneumocystis carinii pneumonia (PCP), is the most common opportunistic infection affecting people living with HIV. As PJP can cause life threatening serious infection to a patient, treatment should not be delayed for these cases. To study clinico-cytomorphological spectrum of PJP.

Material and Methods

We analysed the clinical and detailed cytological features of 15 patients with PJP who were diagnosed on examination of bronchoalveolar lavage (BAL) fluid.

Results

The mean age of the patients was 38.4 years (range 13 - 61 years). A total of seven patients were HIV positive; five patients were post renal transplant, and one patient was a known case of acute leukaemia on immunosuppression. Presence of foamy alveolar casts (FACs) was the distinctive feature and was noted in 14 out of 15 cases. We detected 14 out of 15 cases accurately in BAL fluid cytology.

Conclusion

BAL cytology is one of the important modes of investigations which can detect PJP infection. The history of fever, cough, immunosuppression, bilateral haziness in the radiography of lung and the characteristic alveolar cast indicate the possibility of PJP infection. Cytology can provide early diagnosis and can reduce the mortality of immunocompromised patients.

Delftia acidovorans pneumonia with lung cavities formation

Case Description

A 52-year-old female patient was admitted to our clinic with complaints of cough, sputum, fever and fatigue. The patient has been receiving immunosuppressive therapy for thrombocytopenic purpura for 5 years.

Clinical Finding

Inspiratory crackles were heard on both hemithorax. Oxygen saturation measured with the pulse oximeter was 97%. Chest X-ray showed diffuse reticular opacities that were more prominent in the upper zones of both lungs. WBC counts were 17,600 mm³ and Platelet counts were 29,000 mm³. Thorax CT showed that there were many thin-walled cavities and millimetric nodules accompanied by ground-glass infiltrates in the upper and middle lobes. Gram staining of bronchial fluid, taken by bronchoscopy, revealed Gram-negative bacilli and intense polymorphonuclear leukocytes. The bacteria were defined as Delftia acidovorans by BD Phoenix automated system.

Treatment and outcomes

The patient was hospitalized with suspicion of opportunistic pulmonary infections and cavitary lung disease. After the empirical treatment of intravenous piperacillin-tazobactam and oral clarithromycin, her clinical and radiological findings significantly regressed, and she was discharged with outpatient follow-up.

Clinical Relevance

This is the first example of cavitary pneumonia due to Delftia acidovorans in an immunocompromised patient. We would like to emphasize that Delftia pneumonia should be considered in the differential diagnosis of pulmonary cavitary involvement in such patients.

Utility of fiber-optic bronchoscopy in pulmonary infections among abdominal solid-organ transplant patients: A comprehensive review

Pulmonary infections are frequent complications in abdominal solid-organ transplantation (aSOT) which may threaten patient and allograft survival. Accurate diagnosis and treatment of pulmonary infections in this population can be challenging. Immunosuppressive therapy not only increases the risk of acquiring opportunistic and non-opportunistic infections, but it also impairs the inflammatory responses associated with microbial invasion which in an otherwise normal host produce clinical and radiologic responses that allow for early identification of the offending pathogen. Serologic testing is not a reliable diagnostic modality. Direct microbiological sampling is often necessary to make a definitive diagnosis early in the clinical course to optimize timely, targeted therapy while reducing the risk of developing antimicrobial resistance, and minimize adverse effects of therapy, if any. Fiber-optic bronchoscopy (FOB) with bronchoalveolar lavage (BAL) or transbronchial lung biopsy (TBB) offers such diagnostic advantage and possesses a potential therapeutic value too. This comprehensive review discusses the potential benefits of FOB alongside its risks and complications, indications and contraindications, and techniques. Additionally, the essay highlights FOB's utility and yield specifically with regard to type and timing of infections in aSOT patients.

Usefulness of cellular analysis of bronchoalveolar lavage fluid for predicting the etiology of pneumonia in critically ill patients

Background

The usefulness of bronchoalveolar lavage (BAL) fluid cellular analysis in pneumonia has not been adequately evaluated. This study investigated the ability of cellular analysis of BAL fluid to differentially diagnose bacterial pneumonia from viral pneumonia in adult patients who are admitted to intensive care unit.

Methods

BAL fluid cellular analysis was evaluated in 47 adult patients who underwent bronchoscopic BAL following less than 24 hours of antimicrobial agent exposure. The abilities of BAL fluid total white blood cell (WBC) counts and differential cell counts to differentiate between bacterial and viral pneumonia were evaluated using receiver operating characteristic (ROC) curve analysis.

Results

Bacterial pneumonia (n = 24) and viral pneumonia (n = 23) were frequently associated with neutrophilic pleocytosis in BAL fluid. BAL fluid median total WBC count (2,815/µL vs. 300/µL, P<0.001) and percentage of neutrophils (80.5% vs. 54.0%, P = 0.02) were significantly higher in the bacterial pneumonia group than in the viral pneumonia group. In ROC curve analysis, BAL fluid total WBC count showed the best discrimination, with an area under the curve of 0.855 (95% CI, 0.750–0.960). BAL fluid total WBC count ≥510/µL had a sensitivity of 83.3%, specificity of 78.3%, positive likelihood ratio (PLR) of 3.83, and negative likelihood ratio (NLR) of 0.21. When analyzed in combination with serum procalcitonin or C-reactive protein, sensitivity was 95.8%, specificity was 95.7%, PLR was 8.63, and NLR was 0.07. BAL fluid total WBC count ≥510/µL was an independent predictor of bacterial pneumonia with an adjusted odds ratio of 13.5 in multiple logistic regression analysis.

Conclusions

Cellular analysis of BAL fluid can aid early differential diagnosis of bacterial pneumonia from viral pneumonia in critically ill patients.

Diagnostic bronchoscopy in solid-organ and hematopoietic stem cell transplantation

Fiberoptic bronchoscopy is a valuable diagnostic tool in solid-organ and hematopoietic stem cell transplant recipients presenting with a range of pulmonary complications. This article provides a comprehensive overview of the utility and potential adverse effects of diagnostic bronchoscopy for transplant recipients. Recommendations are offered on the selection of patients, the timing of bronchoscopy, and the samples to be obtained across the spectrum of suspected pulmonary complications of transplantation. Based on review of the literature, the authors recommend early diagnostic bronchoscopy over empiric treatment in transplant recipients with evidence of certain acute, subacute, or chronic pulmonary processes. This approach may be most critical when an underlying infectious etiology is suspected. In the absence of prompt diagnostic information on which to base effective treatment, the risks associated with empiric antimicrobial therapy, including medication side effects and the development of antibiotic resistance, compound the potential harm of delaying targeted management.

Diagnostic yield of bronchoscopic sampling in febrile neutropenic patients with pulmonary infiltrate and haematological disorders

BACKGROUND

The development of pulmonary infiltrate in neutropenic patients is potentially life-threatening, and requires early diagnosis and treatment. Bronchoscopic sampling is an established form of investigation in such patients.

AIM

The aim of the study is to determine the diagnostic yield and complication rate of bronchoscopic sampling in patients with a haematological disorder presenting with febrile neutropenia and pulmonary infiltrate.

METHODS

Medical records and laboratory investigations were retrospectively reviewed for all patients with a haematological disorder who underwent flexible bronchoscopy and bronchoalveolar lavage (BAL) or bronchial washing (BW) at Auckland City Hospital, New Zealand, after presenting with febrile neutropenia and pulmonary infiltrate between January 2008 and December 2009. Demographic, clinical, radiological and microbiological data, procedure-related complications and treatment were recorded. Modifications to treatment regimens as a result of bronchoscopy and 30-day mortality were recorded.

RESULTS

Out of 678 bronchoscopies performed during this period, 26 were in patients with a haematological disorder presenting with febrile neutropenia and pulmonary infiltrate. Most patients had a haematological malignancy (19/26). Two (7.7%) patients reported minor haemoptysis. No biopsies were performed. Positive microbiological samples were obtained with BAL/BW in 23% of patients. The most common organisms identified were Aspergillus species (15.4%); other organisms were Candida (11.6%) and Streptococcus pneumoniae (3.9%). The bronchoscopic results altered the clinical management of 10 (38.4%) patients. The 30-day mortality rate was 19.2%, but no deaths were related to the procedure.

CONCLUSIONS

In haematology patients presenting with febrile neutropenia and pulmonary infiltrate, bronchoscopy is a safe procedure that plays a significant role in management.

Pulmonary infections in transplant recipients

PURPOSE OF REVIEW

Hematopoietic stem cell as well as solid-organ transplantation is being carried out with increasing frequency throughout the world. Lower respiratory tract infections (LRTIs) remain a common life-threatening complication faced by the transplant recipients. The purpose of this review is to provide up-to-date information on pulmonary infections among the transplant recipients, especially emphasizing the endemicity of microorganisms, epidemiology, work-up of infections, and principles of their management.

RECENT FINDINGS

A lower respiratory tract infection such as pneumonia is the most frequent of all the infections and is associated with high morbidity and mortality. Factors increasing the risk of pulmonary infections include surgical techniques, immune status, chemoradiotherapy, alloimmune mechanisms between the host and the graft, and the environment. A high degree of suspicion, computed tomography (CT) scan of the chest, and flexible bronchoscopy are required in most to establish the diagnosis.

SUMMARY

Proper management of LRTI in transplant recipients requires a high degree of suspicion, thorough knowledge of the epidemiology and endemicity of the suspected organisms, CT scan of the chest, and expertise at bronchoscopy. Utmost teamwork among transplant physicians, infectious disease specialist, and bronchoscopist is essential.

BAL neutrophils, serum procalcitonin, and C-reactive protein to predict bacterial infection in the immunocompromised host

BACKGROUND

Bacterial pulmonary infection is a common life-threatening complication in immunocompromised patients. The results of BAL cultures are not immediately available, and their microbiological yield might be limited by empiric antibiotic prescriptions. We evaluated clinical signs and symptoms, leukocyte counts, C-reactive protein (CRP) levels, procalcitonin levels, and BAL fluid neutrophil percentages as potential markers for bacterial infection in a cohort of immunocompromised patients with pulmonary complications.

METHODS

One hundred seven consecutive patients who had been referred for bronchoscopy due to suspected pulmonary infection were included in this study. Based on clinical, laboratory, radiologic, microbiological, and histologic results, patients were classified as having proven bacterial infection (n = 27), possible bacterial infection (n = 11), and no bacterial infection (n = 69).

RESULTS

Most common underlying conditions were hematologic malignancy (n = 62) and solid organ transplantation (n = 20). Clinical parameters were similar in patients with and without bacterial infection (difference was not significant). The percentage of BAL fluid neutrophils had the highest area under the curve (0.818; 95% confidence interval [CI], 0.700 to 0.935; p < 0.001), followed by absolute neutrophil counts (0.797; 95% CI, 0.678 to 0.916; p < 0.001), procalcitonin level (0.746; 95% CI, 0.602 to 0.889; p = 0.001), and CRP level (0.688; 95% CI, 0.555 to 0.821; p = 0.015) to predict proven bacterial infection (in opposition to no or possible bacterial infection) in the receiver operating characteristic analysis. Conversely, neither infiltrates (p = 0.123) nor leukocyte counts (p = 0.429) were useful in diagnosing bacterial infection. The percentage of BAL fluid neutrophils and procalcitonin level were independent predictors of bacterial infection in the multivariate regression.

CONCLUSIONS

Neutrophil percentage in BAL fluid, procalcitonin level, and CRP level might be potentially useful to differentiate bacterial infection from nonbacterial conditions in immunocompromised hosts with pulmonary complications.

Spectrum of Pulmonary Infections in Renal Transplant Recipients in the Tropics: A Single Center Study

BACKGROUND

Pulmonary infections have been implicated as the most common cause of infection related mortality in renal transplant recipients. An appropriate empirical treatment of post transplant pulmonary infections requires knowledge of the spectrum of the microorganisms involved in causing these infections. Besides this knowledge, an aggressive diagnostic approach including the use of invasive tests is often essential to make an early diagnosis for instituting timely and appropriate therapy. We carried out a prospective cohort study to analyze the spectrum of pulmonary infections in these patients and study the utility of bronchoalveolar lavage (BAL) in the diagnosis of the same.

METHODS

From September 2001 to December 2002, 428 patients were under follow up with the department. In all, 40 renal transplant recipients reported with 44 episodes of pulmonary infection during this study period. All patients underwent detailed and appropriate investigations including specific laboratory tests, sputum analysis, X-ray chest, CT and BAL. The spectrum of the causative organisms and the utility of BAL as compared to the other methods of diagnosis were studied and compared.

RESULTS

Out of the 44 episodes of pulmonary infection evaluated, single causative organism could be found in only 24 (54.5%) episodes and multiple etiologies were found in 15 (34.1%) episodes. No definitive cause could be found in 5 episodes. Out of 57 organisms isolated in the 44 episodes, 20 (45.4 %) were bacteria, 16 (36.3 %) each were M. tuberculosis and fungus, 3 were CMV infection and 2 were nocardia. BAL gave a diagnostic yield of 75.8% (25 out of 33 cases). Nine of forty patients died (mortality rate 22.5%) of which 6 deaths could be attributed directly to pulmonary infection. Out of these 9 patients who died, cause of pulmonary infection was bacterial in 5, fungal in 2 and CMV disease in 1. In one patient, organism could not be isolated.

CONCLUSIONS

Our study has shown that more than 1/3rd of pulmonary infections in renal transplant recipients can be attributed to multiple organisms. Bacterial infections were the commonest cause of post transplant pulmonary infection. Tuberculosis is common cause of pulmonary infection in these patients in our set up. Because of its high diagnostic yield, BAL should be considered in all patients with suspected pulmonary infections in the post transplant period.

Fungal infections as a complication of therapy for sarcoidosis

BACKGROUND

Treatment of symptomatic sarcoidosis usually includes systemic immunosuppressive agents. These agents may render the patient more susceptible to opportunistic infections. In addition, the fungal infection may be difficult to distinguish from the underlying sarcoidosis.

AIM

To examine the presentation and management of invasive fungal infections in sarcoidosis patients.

DESIGN

Retrospective record review.

METHODS

We reviewed the notes of all sarcoidosis patients (n = 753) seen at our clinic over an 18-month period.

RESULTS

Seven patients (0.9%) with previously diagnosed sarcoidosis developed fungal infections: two each with Histoplasma capsulatum and Blastomyces dermatitidis and three others with Cryptococcus neoformans. No cases of invasive aspergillus or tuberculosis were identified. The diagnosis of fungal infection was made by bronchoscopy (four cases), open-lung biopsy (one case), bone-marrow aspirate (one case), and spinal fluid examination (one case). All patients were receiving corticosteroids at the time of worsening chest X-ray or clinical status. Four patients were also receiving methotrexate prior to infection. No patient with systemic fungal infection was receiving either infliximab or cyclophosphamide. All patients responded to anti-fungal therapy and a reduction in immunosuppression.

DISCUSSION

Fungal infections occur rarely in treated patients with sarcoidosis. Deterioration of chest X-ray, especially a localized infiltrate, warrants investigation.

Clinical usefulness of bronchoalveolar lavage in heart transplant recipients with suspected lower respiratory tract infection

BACKGROUND

Bronchoscopy with bronchoalveolar lavage (BAL) is the recommended initial invasive diagnostic procedure when lower respiratory tract infection is suspected in solid-organ transplant recipients. In this study, we evaluated the clinical impact and safety of bronchoscopy with BAL in heart transplant recipients.

METHODS

We reviewed all 44 consecutive diagnostic bronchoscopies with BAL that were performed in 35 heart transplant recipients at Helsinki University Central Hospital between May 1988 and December 2001.

RESULTS

Bronchoscopy findings established specific microbiologic diagnoses in 18 of 44 (41%) cases, and 14 of 44 (32%) bronchoscopic findings led to changes in therapy. The diagnostic yield of bronchoscopy from 1 to 6 months after transplantation was 73%, significantly better (p = 0.002) than diagnostic yield during the first month (18%) and after 6 months (28%). Pneumocystis carinii and cytomegalovirus were the most frequently detected pathogens in the BAL fluid. Cytomegalovirus pneumonia carried a high mortality rate (44%), whereas all patients with P carinii pneumonia recovered. Fourteen episodes were diagnosed as bacterial pneumonia, but because of empiric antibiotic therapy that was started widely before bronchoscopy, a microbiologic diagnosis was established in only 1 case. However, all patients with community-acquired pneumonia responded to empiric therapy. Four cases of major complications occurred after bronchoscopy, all cardiovascular but none fatal.

CONCLUSIONS

Bronchoscopy with BAL is a useful diagnostic tool in heart transplant recipients, especially between 1 and 6 months after transplantation.

Role of flexible bronchoscopy in immunocompromised patients with lung infiltrates

STUDY OBJECTIVE

To study the diagnostic role of flexible bronchoscopy (FB) in immunocompromised patients with pulmonary infiltrates.

DESIGN

Prospective, observational study.

SETTING

Tertiary care hospital.

PATIENTS

A total of 104 consecutive non-HIV-infected immunocompromised patients with lung infiltrates in whom FB was performed.

METHODS

The primary outcome measure was the diagnostic yield of FB, which was derived as the number of the diagnoses made using FB results divided by all final diagnoses. Final diagnoses were established using data from FB, surgical lung biopsy (SLB), and microbiology and serology testing, and by the clinical response to empiric therapy. We also studied the diagnostic yields of individual sampling procedures such as BAL, transbronchial biopsy (TBB), and protected-specimen brush (PSB) sampling.

RESULTS

Overall, 128 diagnoses were made in 104 patients. The overall diagnostic yield of FB was 56.2% (95% confidence interval [CI], 47 to 64%). FB provided at least one diagnosis in 53 of 104 patients (51%; 95% CI, 40 to 62%). FB was more likely to establish the diagnosis when the lung infiltrate was due to an infectious agent (81%; 95% CI, 67 to 90%) than to a noninfectious process (56%; 95% CI, 43 to 67%; p = 0.011). The diagnostic yields of BAL (38%; 95% CI, 30 to 47%) and TBB (38%; 95% CI, 27 to 51%) were similar (p = 0.94). The diagnostic yield of PSB sampling was lower (13%; 95% CI 6 to 24%; p = 0.001) than that of BAL. The combined diagnostic yield of BAL and TBB (70%; 95% CI, 57 to 80%) was higher than that of BAL alone (p < 0.001). Finally, the diagnostic yield of FB with PSB sampling, BAL, and TBB was similar to that of FB with BAL and TBB. The complication rate from FB was 21% (95% CI, 15 to 31%). Minor bleeding (13%) and pneumothorax (4%) were the most common complications.

CONCLUSIONS

FB has a high diagnostic yield in immunocompromised patients with pulmonary infiltrates. Based on our results, we recommend performing TBB in these patients, whenever possible.

The diagnosis of pneumonia in renal transplant recipients using invasive and noninvasive procedures

STUDY OBJECTIVES

We used invasive and noninvasive procedures to determine the causes of pneumonia in renal transplant recipients.

SUBJECTS AND METHODS

We retrospectively surveyed 565 renal transplant recipients (transplants received March 1984 to August 2001) to find those with pneumonia. Noninvasive diagnostic methods included serologic testing, and blood and sputum cultures with stains. Invasive procedures included fiberoptic bronchoscopy and percutaneous transthoracic procedures.

RESULTS

A total of 92 patients were enrolled. Of these, 71 patients had a definite etiologic diagnosis of pneumonia. The major infectious pathogens were bacterial (n = 21) and mixed bacterial infection (n = 10), Mycobacterium tuberculosis (TB) [n = 18], and fungi (n = 8). Noninvasive and invasive procedures led to the diagnosis of pneumonia in 31.5% (n = 29) and 45.6% (n = 42) of patients, respectively. Bronchoscopy was used in 64 patients, with a diagnostic yield of 38 cases (59.3%). Patients were 3.62 times more likely to contract pneumonia within 12 months of renal transplantation than they were > or =12 months thereafter (95% confidence interval, 1.33 to 9.84). Twenty-seven of the 92 patients (29.3%) died. The pneumonia mortality rate has dropped significantly since 1996 (41.8% vs 10.8%, p = 0.002).

CONCLUSION

Both invasive and noninvasive procedures are useful in the diagnosis of pneumonia, with declining mortality, in renal transplant recipients. Bacterial and mixed bacterial infection, TB, and fungal infection are the most common pathogens; cases are most likely to occur within 1 year after renal transplantation.

Pulmonary Infiltrates in the Non-HIV-Infected Immunocompromised Patient

Pulmonary complications remain a major cause of both morbidity and mortality in immunocompromised patients. When such individuals present with radiographic infiltrates, the clinician faces a diagnostic challenge. The differential diagnosis in this setting is broad and includes both infectious and noninfectious processes. Rarely are the radiographic findings classic for one disease, and most potential etiologies have overlapping clinical and radiographic appearances. In recent years, several themes have emerged in the literature on this topic. First, an aggressive approach to identifying a specific etiology is necessary; as a corollary, diagnostic delay increases the risk for mortality. Second, the evaluation of these infiltrates nearly always entails bronchoscopy. Bronchoscopy allows identification of some etiologies with certainty, and often allows for the exclusion of infectious agents even if the procedure is otherwise unrevealing. Third, early use of CT scanning regularly demonstrates lesions missed by plain radiography. Despite these advances, initial therapeutic interventions include the use of broad-spectrum antibiotics and other anti-infectives in order to ensure that the patients is receiving appropriate therapy. With the results of invasive testing, these treatments are then narrowed. Frustratingly, outcomes for immunocompromised patients with infiltrates remain poor.

Hazardous crossing: immunosuppression and nosocomial infections in solid organ transplant recipients

BACKGROUND

During the past decade, ever-increasing numbers of patients have undergone renal, pancreatic, small bowel, hepatic, cardiac, or lung transplantation as therapy for various types of renal disease requiring dialytic therapy. Indications for solid organ transplantation include type I and, rarely, type II diabetes mellitus; hyperalimentation-dependent short gut syndrome; and formerly fatal liver, cardiac, or pulmonary failure. Significant improvements in patient and allograft survival have been observed in all categories. Unfortunately, despite such improved results, the risks of infection related to immunosuppression continue to be substantial.

METHODS

Review of pertinent studies from the English literature.

RESULTS

Suppression of host defenses by exogenous immunosuppressive agents renders patients susceptible to invasion by either resident or environmental bacterial, fungal, viral, and protozoal microbes or parasites. In such patients, invasion of organisms that produce mild infection in nonimmunosuppressed individuals can produce severe, lethal disease. Moreover, even low-virulence microbes may invade, proliferate, and cause disease in the immunosuppressed host; such organisms are referred to as "opportunistic" pathogens when they cause disease under these conditions.

CONCLUSION

Advances in the field of transplantation have been substantial, particularly in the regulation of therapeutic immunosuppression, in prophylactic measures to prevent infection, and in more effective diagnosis and treatment modalities.

Determination of bronchoalveolar lavage leukocyte populations by flow cytometry in patients investigated for respiratory disease

BACKGROUND

Characteristic changes in the proportions of leukocyte populations in bronchoalveolar lavage (BAL) reflect different disease states in the lung. The standard method for examination of BAL leukocytes is by microscopy of cytospin preparations. This method may not be the optimum technique due to difficulties in distinguishing cell types morphologically and due to the low number of cells routinely counted. We hypothesized that flow cytometry (FCM) may be a more precise tool for investigating BAL.

METHODS

100 BALs were performed on 92 patients. All samples were stained using the pan-leukocyte marker (CD45) in combination with a granulocyte marker (CD15) and a cell viability marker (7-aminoactinomycin D). Selected samples were also stained with an eosinophil marker (CD23). These samples were run on an FCM and the results compared with leukocyte differentials obtained by light microscopy of parallel cytospin preparations.

RESULTS

Close correlations between the two methods were demonstrated for the enumeration of all leukocyte subsets, but the coefficient of variation was considerably lower by FCM than by cytospin.

CONCLUSIONS

These findings, combined with the speed of FCM and the ability to perform simple lymphocyte phenotyping, argue in favor of this becoming the method of choice for investigating BAL.

A standardized protocol for the treatment of severe pneumonia in kidney transplant recipients

Although the incidence of pneumonia after kidney transplantation is the lowest among all solid organ transplants, it is associated with high mortality rate (40-50%). We evaluated the efficacy of a protocol consisting of bronco-alveolar-lavage (BAL) for early microbiological diagnosis, reduction of the immunosuppressive therapy, and prompt administration of standardized antibiotic regimen in renal transplant recipients with severe pneumonia. Between 6/1989 and 5/1999, 40 kidney transplant recipients developed 46 episodes of severe pneumonia (hypoxia and/or infiltrate on the chest X-ray). According to protocol, in all these cases, a BAL was immediately performed and empirical antibiotic therapy was initiated with erythromycin and trimethoprim-sulfamethoxazole i.v. Furthermore, the immunosuppressive therapy was drastically reduced. Analyses of BAL fluid included cell differential count, cytopathologic examination and cultures for bacteria, fungi and viruses. Within 48 h, the therapy was switched to proper i.v. antibiotics, if necessary, according to the results of sensitivity testing of BAL specimens. The mortality rate was 12.5% (5 of 40). Mechanical ventilation was required in 20 cases (34.5%) and four of the patients that required intubation died. BAL alone established a diagnosis in 67.4% (31 of 46) of the patients. Bacteria were responsible for 61% of the episodes, with fungi responsible for 29% and viruses for 10%. Seven cases of Pneumocystis carinii pneumonia were treated with the prolongation of the initial therapy. We conclude that a combination of early detection of the responsible pathogen by BAL, aggressive reduction of the immunosuppressive therapy and the immediate empirical administration of erythromycin and trimethoprim-sulfamethoxazole is an effective strategy to treat pneumonia kidney transplantation (KTX) recipients.

Prognostic factors of non-HIV immunocompromised patients with pulmonary infiltrates

STUDY OBJECTIVES

To assess the outcome and the prognostic factors in 200 non-HIV immunocompromised patients with pulmonary infiltrates (PIs).

DESIGN

Prospective observational study.

SETTING

An 800-bed university hospital.

PATIENTS

Two hundred non-HIV immunocompromised patients (hematologic malignancies, 79 patients; hematopoietic stem cell transplants [HSCTs], 61 patients; and solid-organ transplants, 60 patients).

METHODS

Investigation of prognostic factors related to mortality using a multiple logistic regression model.

RESULTS

Specific diagnosis of the PI was obtained in 78% of the cases (infectious origin was determined in 74%). The overall mortality rate was 39% (78 of 200 patients). Patients with HSCT had the highest mortality rate (53%). A requirement for mechanical ventilation (odds ratio [OR], 28; 95% confidence interval [CI], 9 to 93), an APACHE (acute physiology and chronic health evaluation) II score of > 20 (OR, 5.5; 95% CI, 2 to 14.7), and a delay of > 5 days in establishing a specific diagnosis (OR, 3.4; 95% CI, 1.2 to 9.6) were the variables associated with mortality at the multivariate analysis. The subgroup analysis based on underlying disease confirmed the prognostic significance of these variables and the infectious etiology for the PI.

CONCLUSIONS

Mortality in immunocompromised patients is high, particularly in patients undergoing HSCT. Achieving an earlier diagnosis potentially may improve the mortality rate of these patients.

Culturing bronchial washings obtained during bronchoscopy fails to add diagnostic utility to culturing the bronchoalveolar lavage fluid alone

A retrospective analysis was performed to determine whether cultures of bronchial washings (BW) obtained during bronchoscopy added to the diagnostic efficiency of cultures of bronchoalveolar lavage fluid (BAL) alone. Results of BW and BAL cultures submitted from 268 patients over a 7-month period were compared. The isolation of an organism from the BW but not from the BAL occurred in only 17.4% of cases. Moreover, the vast majority of those organisms consisted of yeasts or molds of questionable clinical significance that did not prompt a change in antimicrobial therapy. Culturing the BAL specimen alone would have resulted in an efficiency of 97.0% (95% confidence interval 94.2-98.7%) for the isolation of clinically relevant pathogens identified from bronchoscopic specimens. These results suggest that the submission of BW obtained during the BAL procedure for culture evaluation not only fails to add diagnostic value, but may also result in unnecessary laboratory evaluations and provide misleading information to clinicians.

Aspergillosis in lung transplantation: incidence, risk factors, and prophylactic strategies

Invasive aspergillosis remains a significant cause of morbidity and mortality in transplantation, especially lung and allogeneic bone marrow transplant recipients. The epidemiology, classic and newly recognized risk factors, and incidence of aspergillosis are reviewed. Risk factors include environmental exposures, airway colonization, profound immunosuppression, neutropenia, prior cytomegalovirus infection, and renal dysfunction. Clinical and radiographic presentations of invasive aspergillosis are discussed, including some unusual manifestations in lung transplant recipients. Early and accurate diagnosis of aspergillosis remains a challenge, and diagnostic strategies are reviewed, with an emphasis on the chest computerized tomography scan and on transbronchial or open lung biopsy. Recent advances include prophylactic and pre-emptive antifungal strategies, newer therapeutic agents, and improved risk stratification.

Diagnostic yield of bronchoalveolar lavage following renal transplantation

Organ transplant recipients are at high risk of infectious pulmonary complications. In this retrospective study, the diagnostic yield of bronchoalveolar lavage (BAL) was evaluated in renal transplant recipients. The results were analysed in special regard to the clinical presentation of pulmonary infections and the possible impact of new immunosuppressive agents. Over a 5-year period 91 BAL were performed in 71 renal transplant recipients. Microorganisms were isolated from 69% of BAL (63/91): bacteria 32%; cytomegalovirus (CMV) 27%; Pneumocystis carinii (PC) 22%; other viruses 9% (HSV; EBV, RSV, adenovirus, HHV8); Aspergillus fumigatus 1%. Total cell counts and neutrophil counts in BAL were significantly elevated in bacterial infection, whereas BAL positive for PC showed eosinophilia (P<0.05). There was no association between clinical symptoms and the radiological pattern of infiltrates and the type of infection. Immunosuppression containing tacrolimus or mycophenolate mofetil was associated with a significantly higher percentage of PC and CMV infections compared to cyclosporin-based immunosuppression (65% vs. 30%, P<0.005). A considerable number of PC and CMV infections occurred beyond 6 months after transplantation. In conclusion, BAL has a high diagnostic yield in renal transplant recipients. Infection with CMV and PC should also be considered beyond 6 months after transplantation, and prophylaxis for opportunistic infections should be given if the immunosuppression is intensified.

Lung nodular lesions in heart transplant recipients

To describe the characteristics and etiology of lung nodules after heart transplantation (HT). During a 6-year period 147 patients received HT and 130 survived more than 1 week. Nodular lesions were demonstrated after HT in 13 patients (10%). Median age was 53 years, and all patients were male. Nodules were detected 23 to 158 days after HT (median, 66 days). An etiologic diagnosis was made in all but 1 case: Aspergillus (5), Nocardia-Rhodococcus (4), and cytomegalovirus (CMV) (3). Previous severe infection was present in 50% of the patients and rejection in 33% (75% with nocardiosis). Initially all patients with Nocardia but only 1 patient with aspergillosis were asymptomatic. The most common symptoms were fever (67%) and cough (50%). Central nervous system (CNS) involvement appeared in only one Aspergillus-infected patient. An average of 1.8 diagnostic procedures per patient were performed. Median time to establish a diagnosis was 8 days (0 to 24). Median hospital stay was 36 days and reached 60 in patients with Aspergillus. No patient died, although aspergillosis, which must be suspected in the presence of dyspnea, pleuritic pain, and CNS symptoms, caused the highest morbidity. Overall diagnostic yield was 60% for transtracheal aspiration, 70% for bronchoalveolar lavage, and 75% for transthoracic aspiration. Ten percent of HT patients developed lung nodules that were mainly caused by Aspergillus, Nocardia, and CMV. The time of appearance and some clinical manifestations may suggest the etiology and may help in the empirical treatment.

Diagnosis and Treatment of Opportunistic Infections in Immunocompromised Surgical Patients

The advent of successful therapy for patients who suffer many types of organ dysfunction and failure, malignancies, and acquired immunodeficiency syndrome has led to the concurrent threat of infection due to a wide array of pathogens, particularly opportunistic microbes that rarely cause disease under routine circumstances. Among patients who are subjected to extreme degrees of immunosuppression, almost any type of bacterial, fungal, viral, protozoal, or parasitic organism can exhibit pathogenic potential and lead to devastating consequences for the host. Immunosuppressive drug therapy for the purpose of organ allograft maintenance, cancer chemotherapy, or the human immunodeficiency virus exerts potent effects upon cellular immunity. Therefore, although these groups of patients are more susceptible to all types of infectious disease processes, infections due to those pathogens that require a component of cellular immunity for their eradication, such as fungi and viruses, occur at a higher frequency than that observed among normal individuals. Of critical importance, all types of infections are associated with higher rates of morbidity and mortality in immunosuppressed patients. Currently, improved diagnostic techniques and new treatment modalities have rendered many serious infections, for which suitable therapy previously did not exist, amenable to treatment. Because of the large number of immunosuppressed patients who now lead highly productive lives, it is important for the surgical practitioner to become familiar with the modalities currently available to precisely diagnose and effectively treat opportunistic infections in immunocompromised surgical patients.

Successful management of pulmonary tuberculosis in renal allograft recipients in a single center

BACKGROUND

Pulmonary infections, especially tuberculosis, are responsible for significant mortality and morbidity among renal transplant recipients in developing countries. Conventional diagnostic modalities are associated with a low yield, delaying specific therapy.

METHODS

All patients transplanted within a 1.5-year period were prospectively followed-up for one year. Patients were on a cyclosporine-based triple immunosuppressive regimen. None received isoniazid prophylaxis, and those transplanted in the last seven months of the study period received daily cotrimoxazole. Patients exhibiting unequivocal evidence of pulmonary infections underwent further evaluation. Search for offending organisms was made by sputum examination and bronchoalveolar lavage (BAL).

RESULTS

. Thirty-nine infection episodes were recorded in 34 patients. M. tuberculosis was isolated during 10 episodes, pyogenic bacteria and Pneumocystis carinii in 6 each, candida in 4, aspergillus in 3, cytomegalovirus (CMV) in 3, and nocardia and mucor in one episode each. More than one organism was isolated during five episodes. Bacterial pneumonia and tuberculosis were diagnosed in another seven and two patients, respectively, on the basis of a therapeutic response to specific chemotherapy. Over two thirds of the organisms were identified by examination of BAL fluid. BAL was useful in the diagnosis of tuberculosis and P. carinii pneumonia but was relatively insensitive for CMV and bacterial infections. An increased frequency of acute rejection and higher serum creatinine were factors that predisposed to infections. All patients with pulmonary tuberculosis made a full recovery.

CONCLUSIONS

Tuberculosis and P. carinii are the most common nonpyogenic infections in the first year after transplantation in developing countries. An aggressive search for tubercle bacilli should be made using bronchoscopy and examination of BAL fluid in patients not responding to a short trial of antibiotics. A four-drug regime without rifampicin given for 18 months is effective for pulmonary tuberculosis in patients on cyclosporine. We recommend routine prophylactic use of one single-strength tablet of cotrimoxazole daily for at least six months after transplantation.

The role of fibre-optic bronchoscopy in solid organ, transplant patients with pulmonary infections

Organ transplantation is currently the standard therapy for patients with end-stage organ dysfunction. The immunosuppression caused by this therapy increases the rate of infection, particularly in the lungs. Early diagnosis is extremely important and fibre-optic bronchoscopy is a helpful tool in reaching diagnosis. Knowing the timing of various pathogens following transplantation, and the radiological picture as well as the prophylactic regimen, is helpful when specific pathogens are suspected. Bronchoscopy with bronchoalveolar lavage and transbronchial biopsies are particularly helpful in diagnosis of bacterial cytomegalovirus (CMV) and pneumocytosis carinii pneumocytosis, and is considered a safe procedure. Open lung biopsy is reserved for those who have negative bronchoscopy with a reasonable prognosis.

The diagnosis and treatment challenges in nosocomial pneumonia

Pneumonia is the second most common type of nosocomial infection and is most prevalent in patients who are mechanically ventilated. Nosocomial pneumonia (NP) is the leading contributor to mortality in patients, accounting for approximately 50% of deaths in patients with hospital-acquired infections. Several factors place patients at risk for developing NP, including prolonged length of hospital stay and local epidemiology. Gram-positive pathogens such as Streptococcus pneumoniae and, more recently, Staphylococcus aureus, as well as atypical organisms such as Legionella spp are increasingly associated with NP. Emerging antimicrobial resistance among these organisms confounds treatment interventions. Lack of local definitive information and patient comorbidities further complicate the physician's treatment decisions. The role of invasive pulmonary diagnostic techniques remains problematic and controversial. Studies, however, have shown that early initiation of appropriate empiric therapy is essential to improving patient outcome and reducing mortality. This article will review therapeutic options and appropriate antimicrobial agents for use in the treatment of nosocomial pneumonia in the era of emerging drug resistances.

[Usefulness of bronchoalveolar lavage in the renal transplant patient with suspected respiratory infection]

In this retrospective study we aimed to assess the diagnostic yield of bronchoalveolar lavage (BAL) in kidney transplant patients who were suspected of having severe respiratory infection or in whom empirical antibiotic treatment had failed. All BAL procedures performed on kidney transplanted patients suspected of having respiratory infections between January 1, 1988 and July 31, 1996 were analyzed. BAL was carried out in the standard way and samples were sent for cytologic and bacteriologic study. Thirty-three patients with a mean age of 48.5 years were enrolled. All had been receiving immunosuppressive treatment and the mean time following transplantation was 320 days. Thirty-one had received antibiotic treatment before BAL. BAL was positive for 21 of the 33 patients (64%). Twenty-two pathogens were identified: 6 Pneumocystis carinii, 4 Cytomegalovirus, 3 Mycobacterium tuberculosis, 2 Aspergillus fumigatus, 2 Herpes simplex type I, 1 Streptococcus pneumoniae, 1 Staphylococcus aureus, 1 Streptococcus mitis, 1 Legionella pneumophila, 1 Legionella longbeachae. BAL was negative for 12 patients, of whom 8 were tentatively diagnosed of bacterial infection, 3 of acute pulmonary edema and one of pulmonary infarction. Based on the results, therapy was changed for 20 patients (61%), 19 (58%) because an unsuspected pathogen was identified and 1 because treatment could be simplified. The diagnostic yield of BAL is high (64%) in kidney transplant patients suspected of respiratory infection and is useful for managing such cases, as evidenced by the fact that a high proportion (19/33) of our patients were infected by pathogens not covered by empirical treatment.

Invasive aspergillosis in the immunocompromised host: utility of computed tomography and bronchoalveolar lavage

OBJECTIVE

Bronchoalveolar lavage is performed almost routinely in immunocompromised patients with suspected pneumonia, but it has a low yield in the diagnosis of pulmonary aspergillosis. The aim of this study was to determine whether computed tomography (CT) is helpful in determining the likelihood of a positive bronchoalveolar lavage by allowing distinction of patients with angioinvasive aspergillosis from those with Aspergillus bronchopneumonia.

METHODS AND RESULTS

A retrospective study was performed including consecutive immunocompromised patients with suspected pneumonia who underwent CT scanning of the chest and bronchoalveolar lavage and who had definite diagnosis of pulmonary aspergillosis. The CT scans were reviewed by two chest radiologists and classified as showing features consistent with angioinvasive or airway invasive aspergillosis. Twenty-one patients met the inclusion criteria. Bronchoalveolar lavage was positive for fungi in two of 11 patients with CT findings consistent with angioinvasive aspergillosis and eight of 10 patients with CT scans consistent with Aspergillus bronchopneumonia (P < 0.01, chi-squared test). CT findings of angioinvasive aspergillosis included nodules measuring 1-3.5 cm in diameter in six, segmental consolidation in three, and both nodules and segmental consolidation in two patients. CT findings of Aspergillus bronchopneumonia including peribronchial consolidation in five, small centrilobular micronodules in one, and both in four patients.

CONCLUSIONS

Chest CT is helpful in determining the likelihood of successful diagnosis of pulmonary aspergillosis by bronchoalveolar lavage.

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.

Use of bronchoalveolar lavage semiquantitative cultures in cystic fibrosis

To assess bronchoalveolar lavage (BAL) in adult CF patients with respiratory symptoms, we studied BAL fluid (BALF) culture results from 28 bronchoscopies in 11 patients. Patients were asked to provide sputum for culture. All but two patients were receiving antibiotics at the time of bronchoscopy, with 13 bronchoscopies done on patients who had been receiving antibiotics for more than 10 d. Gram stain of the BALF was positive in 18 cases. In all but one BALF, > 10,000 colony-forming units per milliliter (cfu/ml) BALF of one or more pathogens was identified. The final case grew Burkholderia cepacia, which was not grown in the sputum. In only six cases (21%) were the sputum and BALF culture results the same. Prior to 11 bronchoscopies, the sputum was not adequate. The remaining 11 cases either had different pathogens in the BAL (six cases), or had some but not all of the BALF pathogens in the sputum. BALF cultures changed therapy in 13 (48%) of cases. Semiquantitative culture of BALF was a useful diagnostic tool in CF in patients in whom empiric therapy failed.

Differential cytology of bronchoalveolar lavage fluid in immunosuppressed children with pulmonary infiltrates

OBJECTIVE

Bronchoalveolar lavage (BAL) is a well established technique for the detection of pathogens in immunosuppressed children, but its diagnostic yield is variable. The aim of this study was to investigate whether BAL differential cell counts are helpful in the evaluation of pulmonary infiltrates in immunocompromised children.

STUDY DESIGN

BAL was performed 28 times in 27 febrile immunocompromised children with pulmonary infiltrates. All patients were pretreated with broad spectrum antibiotics; 11 children also received amphotericin B. BAL was conducted with a flexible bronchoscope wedged in the area of maximal pathology as suggested by the chest radiograph or in the middle lobe in patients with diffuse interstitial radiographic changes. Differential cell counts were performed from cell smears obtained after centrifugation of BAL fluid.

RESULTS

Bacterial or fungal organisms were detected in BAL fluid of 12 patients. Patients with bacterial or fungal infections (group 1) had a significantly higher percentage of granulocytes in BAL fluid both compared with patients with sterile BAL cultures (group 2) and with a control group of children without pulmonary disease (p < 0.001, Wilcoxon test). The proportion of lymphocytes was not different from the control group in group 1 but significantly increased in group 2 (p < 0.001, Wilcoxon test). Blood differential cell counts were not different in the two patient groups. Lymphocyte subsets of BAL fluid obtained in a subgroup of patients were not significantly different from controls.

CONCLUSION

These data suggest that BAL differential cell counts may be a useful adjunct in the differential diagnosis of pulmonary infection in immunocompromised children.

Diagnostic value of protected BAL in diagnosing pulmonary infections in immunocompromised patients

STUDY OBJECTIVES

To assess the diagnostic utility of protected BAL (P-BAL) in respiratory infections in immunocompromised patients and to examine whether P-BAL alone could substitute the combined use of protected specimen brush (PSB) and BAL in such patients.

PATIENTS AND STUDY DESIGN

Thirty-seven immunocompromised patients who underwent PSB, P-BAL, and BAL simultaneously for the diagnosis or exclusion of bacterial or nonbacterial opportunistic respiratory infections were studied prospectively. The P-BAL was performed through the inner catheter of a telescoping plugged catheter with 60 mL of saline solution.

MAIN RESULTS

Thirteen (35%) cases of bacterial pneumonia were diagnosed. PSB obtained seven true-positive (TP) results, P-BAL obtained nine, and BAL obtained eight TP. Results of the three techniques were positive and concordant in 6 of the 13 cases. PSB remained free of contamination from oropharyngeal flora in all cases, P-BAL was contaminated twice, and BAL was contaminated in four cases. Opportunistic respiratory infections were diagnosed in 19 patients. P-BAL results were identical to those with BAL in all cases: 18 TP and 1 false-negative. The average volume of P-BAL fluid retrieved was 19 mL, sufficient for all microbiologic and cytologic processings. P-BAL was more time-consuming than both PSB and BAL procedures and was technically more complex.

CONCLUSION

P-BAL alone can substitute the combined use of both PSB and BAL in immunocompromised patients and attains a higher sensitivity than PSB in diagnosing bacterial pneumonia. The combined strategy continues to be a good choice, but due to the high incidence of bacterial pneumonia in these patients, a highly efficient diagnostic procedure is required not only for nonbacterial opportunistic respiratory infections but also for bacterial pneumonia.