Sputum induction for the diagnosis of pulmonary disease in HIV positive patients

Expiratory Technique versus Tracheal Suction to Obtain Good-Quality Sputum from Patients with Suspected Lower Respiratory Tract Infection: A Randomized Controlled Trial

Microbiological diagnostics of good-quality sputum samples are fundamental for infection control and targeted treatment of lower respiratory tract infections (LRTI). This study aims to compare the expiratory technique and tracheal suction on the quality of sputa from adults acutely hospitalized with suspected LRTI. We performed an open-label, randomized controlled trial. Patients were randomized to sputum sampling by tracheal suction (standard care) or the expiratory technique. The primary outcome was quality of sputum evaluated by microscopy and was analysed in the intention-to-treat population. The secondary outcomes were adverse events and patients experience. In total, 280 patients were assigned to tracheal suction (n = 141, 50.4%) or the expiratory technique (n = 139, 49.6%). Sputum samples were collected from 122 (86.5%) patients with tracheal suction and 67 (48.2%) patients with expiratory technique. Good-quality sputa were obtained more often with tracheal suction than with expiratory technique (odds ratio 1.83 [95% CI 1.05 to 3.19]; p = 0.035). There was no statistical difference in adverse events (IRR 1.21 [95% CI, 0.94 to 1.66]; p = 0.136), but patient experience was better in the expiratory technique group (p < 0.0001). In conclusion, tracheal suction should be considered a routine procedure in emergency departments for patients with suspected LRTI.

Performance of a Real Time PCR for Pneumocystis jirovecii Identification in Induced Sputum of AIDS Patients: Differentiation between Pneumonia and Colonization

Pneumocystis jirovecii pneumonia (PcP) remains an important cause of morbimortality worldwide and a diagnostic challenge. Conventional methods have low accuracy, hardly discriminating colonization from infection, while some new high-cost or broncho-alveolar lavage-based methods have limited usefulness in developing countries. Quantitative PCR (qPCR) tests may overcome these limitations due to their high accuracy, possibility of automation, and decreasing cost. We evaluated an in-house qPCR targeting the fungus mtSSU gene using induced sputum. Sensitivity of the assay (ten target gene copies/assay) was determined using recombinant plasmids. We prospectively studied 86 AIDS patients with subacute respiratory symptoms in whom PcP was suspected. qPCR results were determined as quantification cycles (Cq) and compared with a qualitative PCR performed in the same IS, serum 1,3-β-D-Glucan assay, and a clinical/laboratory/radiology index for PcP. The qPCR clustered the patients in three groups: 32 with Cq ≤ 31 (qPCR+), 45 with Cq ≥ 33 (qPCR-), and nine with Cq between 31-33 (intermediary), which, combined with the other three analyses, enabled us to classify the groups as having PcP, not P. jirovecii-infected, and P. jirovecii-colonized, respectively. This molecular assay may contribute to improve PcP management, avoiding unnecessary treatments, and our knowledge of the natural history of this infection.

Diagnostic value of direct fluorescence antibody staining for detecting Pneumocystis jirovecii in expectorated sputum from patients with HIV infection

Direct fluorescent antibody (DFA) staining of induced sputum is frequently used to diagnose Pneumocystis pneumonia (PCP) in patients infected with human immunodeficiency virus, although induction can provoke nausea and bronchospasm. Since the diagnostic value of expectorated sputum examined with DFA stain has not been well evaluated, we reviewed the medical records of HIV-infected patients who were clinically diagnosed as having PCP between 1999 and 2011. Over this 13-year period, we found 76 patients whose records included the results of DFA staining of expectorated sputum and noted that 42 (55.3%) were positive. Polymerase chain reaction to detect Pneumocystis in the sputum of 65 of the patients resulted in the finding of 43 (66.2%) who were positive. Our findings suggest that DFA staining of expectorated sputum could be a useful initial diagnostic method in HIV-infected patients with PCP.

"Induced sputum versus gastric lavage for the diagnosis of pulmonary tuberculosis in children"

Background

Diagnosis of pulmonary tuberculosis (PTB) is difficult in infants and young children. For microbiological confirmation of PTB children, sequential gastric lavage (GL) is recommended. Induced sputum (IS) may be an alternative or complementary tool, but the information is limited in children in developed countries. The aim of this study is to assess the safety and diagnostic yield from IS combined with GL for PTB diagnosis in non-HIV infected children.

Methods

The study involved 22 children with suspected PTB admitted to the Getafe Hospital from January 2007 to May 2011. IS and GL were performed on three consecutive days, according to a standardized protocol. In all samples, BK staining, culture and PCR were carried out, including Genotype MTBDR plus for resistance to INH-RIF (Isoniazid-Rifampin) since 2008. A preliminary analysis of an ongoing prospective study is presented.

Results

Median age was 72 months (range 1 month to 14 years of age). Seven (33%) were ≤ 5 years of age. Seventeen were clinically diagnosed of PTB based on positive PPD and radiological criteria. Microbiological confirmation was achieved in 10 (58.8%) by either GL or IS. M. tuberculosis was identified by GL in 8 children (47.1%) and by IS in 7 (41.2%). One infant (2 IS samples) had transient oxygen desaturation recovered spontaneously.

Conclusions

IS appears to be safe and well tolerated by children for diagnosis of PTB and is more convenient. Increasing the diagnostic yield of PTB in children with PTB may be a complementary technique. Largest studies are necessary to define the role of IS in paediatric PTB.

Blood (1->3)-beta-D-glucan as a diagnostic test for HIV-related Pneumocystis jirovecii pneumonia

(See the editorial commentary by Morris and Masur, on pages 203-204.)

BACKGROUND

Improved noninvasive diagnostic tests for Pneumocystis jirovecii pneumonia (PCP) are needed. We evaluated the test characteristics of plasma (1 → 3)-β-D-glucan (β-glucan) for HIV-related PCP among a large group of patients presenting with diverse opportunistic infections (OIs).

METHODS

The study population included all 282 participants in AIDS Clinical Trials Group A5164, a study of early versus deferred antiretroviral therapy in conjunction with initial therapy of acute OIs. Baseline plasma samples were assayed for β-glucan, with standard assay reference values defining ≥ 80 pg/mL as positive. Before this analysis, diagnosis of PCP was independently adjudicated by 2 study investigators after reviewing reports from study sites.

RESULTS

A total of 252 persons had a β-glucan result that could be analyzed, 173 (69%) of whom had received a diagnosis of PCP. Median β-glucan with PCP was 408 pg/mL (interquartile range [IQR], 209-500 pg/mL), compared with 37 pg/mL (IQR, 31-235 pg/mL) without PCP (P < .001). The sensitivity of β-glucan dichotomized at 80 pg/mL for the diagnosis of PCP was 92% (95% confidence interval [CI], 87%-96%), and the specificity was 65% (95% CI, 53%-75%); positive and negative predictive values were 85% (95% CI, 79%-90%) and 80% (95% CI, 68%-89%) respectively, based on the study prevalence of 69% of patients with PCP. Rates of abnormal lactate dehyrogenase levels did not differ significantly between those with and without PCP.

CONCLUSIONS

Blood (1 → 3)-β-D-glucan is strongly correlated with HIV-related PCP. In some clinical centers, this may be a more sensitive test than the induced sputum examination and could reduce the need for both bronchoscopy and empirical therapy of PCP.

Nasopharyngeal aspiration for diagnosis of pulmonary tuberculosis

BACKGROUND

Confirmation of pulmonary tuberculosis (PTB) in young children is difficult as they seldom expectorate sputum.

AIM

To compare sputa obtained by nasopharyngeal aspiration and by sputum induction for staining and culture of Mycobacterium tuberculosis.

PATIENTS AND METHODS

Patients from Mulago Hospital, Kampala with symptoms suggestive of PTB were considered for inclusion in the study. Those with a positive tuberculin test and/or a chest radiograph compatible with tuberculosis were recruited. Infection with human immunodeficiency virus (HIV) was confirmed by duplicate enzyme-labelled immunosorbent assay or in children <15 months by polymerase chain reaction (PCR). Direct PCR was undertaken on 82 nasopharyngeal aspirates.

RESULTS

Of 438 patients referred, 94 were recruited over a period of 5 months. Median (range) age was 48 (4-144) months. Of 63 patients tested, 69.8% were infected with HIV. Paired and uncontaminated culture results were available for 88 patients and smear results for 94 patients. Nasopharyngeal aspirates were smear-positive in 8.5% and culture-positive in 23.9%. Induced sputa were smear-positive in 9.6% and culture positive in 21.6%. Overall, 10.6% were smear-positive, 25.5% were culture-positive and 26.6% had smear and/or culture confirmed tuberculosis. Direct PCR on nasopharyngeal aspirates had a sensitivity of 62% and specificity of 98% for confirmation of culture-positive tuberculosis.

CONCLUSIONS

Nasopharyngeal aspiration is a useful, safe and low-technology method for confirmation of PTB and, like sputum induction, can be undertaken in outpatient clinics.

Improved survival for HIV infected patients with severe Pneumocystis jirovecii pneumonia is independent of highly active antiretroviral therapy

BACKGROUND

Despite a decline in incidence of Pneumocystis jirovecii pneumonia (PCP), severe PCP continues to be a common cause of admission to the intensive care unit (ICU) where mortality remains high. A study was undertaken to examine the outcome from intensive care for patients with PCP and to identify prognostic factors.

METHODS

A retrospective cohort study was conducted of HIV infected adults admitted to a university affiliated hospital ICU between November 1990 and October 2005. Case note review collected information on demographic variables, use of prophylaxis and highly active antiretroviral therapy (HAART), and hospital course. The main outcome was 1 month mortality, either on the ICU or in hospital.

RESULTS

Fifty nine patients were admitted to the ICU on 60 occasions. Thirty four patients (57%) required mechanical ventilation. Overall mortality was 53%. No patient received HAART before or during ICU admission. Multivariate analysis showed that the factors associated with mortality were the year of diagnosis (before mid 1996 (mortality 71%) compared with later (mortality 34%; p = 0.008)), age (p = 0.016), and the need for mechanical ventilation and/or development of pneumothorax (p = 0.031). Mortality was not associated with sex, ethnicity, prior receipt of sulpha prophylaxis, haemoglobin, serum albumin, CD4 count, PaO2, A-aO2 gradient, co-pathology in bronchoscopic lavage fluid, medical co-morbidity, APACHE II score, or duration of mechanical ventilation.

CONCLUSIONS

Observed improved outcomes from severe PCP for patients admitted to the ICU occurred in the absence of intervention with HAART and probably reflect general improvements in ICU management of respiratory failure and ARDS rather than improvements in the management of PCP.

O escarro induzido no diagnóstico das doenças pulmonares em pacientes positivos ao vírus da imunodeficiência humana

INTRODUÇÃO: O escarro induzido é utilizado para monitorar a inflamação de vias aéreas, porém seu papel como ferramenta diagnóstica de doenças pulmonares em pacientes imunocomprometidos ainda necessita de melhor definição. OBJETIVOS: Determinar o rendimento do escarro induzido no diagnóstico das doenças pulmonares em pacientes positivos ao virus da imunodeficiência humana (HIV). MÉTODO: No período de janeiro de 2001 a setembro de 2002, foram avaliados todos os pacientes com idade superior a 14 anos, infectados com o HIV, admitidos em Hospital de Referência. Foram incluídos aqueles indivíduos que apresentavam manifestações clínicas do aparelho respiratório há pelo menos 7 dias, associadas, ou não, a alterações radiológicas, bem como indivíduos assintomáticos do ponto de vista respiratório, com alterações no radiograma de tórax. Os pacientes foram submetidos à avaliação clínica, radiológica e laboratorial e realizaram a indução de escarro, seguida pela broncofibroscopia, lavado broncoalveolar e biópsia pulmonar transbrônquica. As amostras foram processadas para bacterioscopia pelo método de Gram e Ziehl-Neelsen, cultura quantitativa para bactérias, exame micológico direto, cultura para micobactérias e fungos, pesquisa de citomegalovírus e Pneumocystis jiroveci, bem como celularidade total e diferencial. RESULTADOS: 54 pacientes foram incluídos no estudo. A pesquisa de agente etiológico resultou negativa em 7 pacientes, sendo que nos casos restantes foram isolados 60 agentes. Dentre os agentes isolados, 46,7% foram P. jiroveci; 33,5% bactérias piogênicas e 16,7% Mycobacterium tuberculosis. O escarro induzido apresentou sensibilidade de 57,5%, especificidade de 42,9%, valor preditivo positivo de 87,1%, valor preditivo negativo de 13% e acurácia de 55,6%. CONCLUSÕES: Nesta população, a análise do escarro induzido é um procedimento simples, seguro e com bom rendimento diagnóstico.

The Utility of Sputum Induction for Diagnosis of Pneumocystis Pneumonia in Immunocompromised Patients without Human Immunodeficiency Virus

Sputum induction for the diagnosis of Pneumocystis pneumonia (PCP) is widely used for patients with acquired immunodeficiency syndrome (AIDS), but its utility for patients with other forms of immunocompromise is less well defined. Immunocompromised patients with PCP who do not have human immunodeficiency virus (HIV) infection have a lower burden of organisms, and sputum induction may consequently have lower diagnostic yield in these patients. However, this retrospective review of the experience at a tertiary referral center suggests that sputum induction has clinical utility for diagnosing PCP in immunocompromised patients without HIV infection.

Pneumocystis carinii f. sp. hominis DNA in immunocompetent health care workers in contact with patients with P. carinii pneumonia

The possible transmission of Pneumocystis carinii f. sp. hominis from patients with P. carinii pneumonia to asymptomatic health care workers (HCW), with or without occupational exposure to human immunodeficiency virus (HIV)-infected patients with P. carinii pneumonia, was examined. HCW in a specialist inpatient HIV-AIDS facility and a control group in the general medical-respiratory service in the same hospital provided induced sputum and/or nasal rinse samples, which were analyzed for the presence of P. carinii f. sp. hominis DNA by using DNA amplification (at the gene encoding the mitochondrial large subunit rRNA [mt LSU rRNA]). P. carinii f. sp. hominis DNA was detected in some HCW samples; those with the closest occupational contact were more likely to have detectable P. carinii DNA. P. carinii DNA was detected in one HCW who carried out bronchoscopy over a 2-year period. P. carinii-positive samples were genotyped by using DNA sequence variations at the internal transcribed spacer (ITS) regions of the nuclear rRNA operon, along with bronchoalveolar lavage samples from patients with P. carinii pneumonia hospitalized at the same time. Genotyping identified 31 different P. carinii f. sp. hominis ITS genotypes, 26 of which were found in the patient samples. Five of the eight ITS genotypes detected in HCW samples were not observed in the patient samples. The results suggested that HCW in close occupational contact with patients who had P. carinii pneumonia may have become colonized with P. carinii. Carriage was asymptomatic and did not result in the development of clinical disease.

Effect of sputum induction by hypertonic saline on specimen quality

Microbiologic work-up of expectorated material is routinely used to search for the etiology of pulmonary infections, but sputum is often contaminated by saliva. Inhalation of hypertonic saline induces bronchial secretions and theoretically may improve specimen quality. We compared in a laboratory-blinded, randomized study the quality of sputum obtained either with induction by saline or without induction in patients with respiratory tract infection and a history of productive cough. The quality of sputum was considered good if the polymorphonuclear neutrophils (PMNs)/squamous epithelial cells (SECs) ratio was > or = 2 or the Q (quality) score was > or = +1 on Gram stain. Forty-nine and 50 patients were able to expectorate in the induced and spontaneous sputum groups, respectively. PMNs/SECs ratio was > or = 2 in 65% and 74% of the patients in the induced and spontaneous sputum groups (p = 0.47); for the Q score, a value > or = +1 was found in 55% and 66% of the patients of each group (p = 0.37). In conclusion, sputum induction by hypertonic saline inhalation does not improve specimen quality as judged by the PMNs/SECs ratio on Gram stain.

Pleural effusions in patients with AIDS

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical aspects of Pneumocystis carinii pneumonia in HIV-infected patients: 1997

In 1997 in Europe P. carinii pneumonia is largely a disease of individuals who are either unaware of their HIV serostatus or who decline prophylaxis despite knowing they are HIV positive. Although fibre optic bronchoscopy and bronchoalveolar lavage is the diagnostic 'gold standard' polymerase chain reaction (PCR) amplification applied to oropharyngeal washings appears to have a moderate to high diagnostic yield. With further development this may provide a truly non-invasive diagnostic test. There is a clear need for an inherently more effective regimen for prophylaxis both for those with adverse reactions (ADR) to co-trimoxazole and also for those with low CD4 lymphocyte counts. Ideally, new drug regimens should afford cross-prophylaxis against bacterial, mycobacterial and other fungal infections. Given the high frequency of ADR to co-trimoxazole when used as treatment for P. carinii pneumonia, there is also a need for effective, non-toxic alternative therapies.

A comparison of induced and expectorated sputum for the diagnosis of Pneumocystis carinii pneumonia

STUDY OBJECTIVES

To compare the sensitivities of expectorated and induced sputum for the diagnosis of Pneumocystis carinii pneumonia (PCP).

DESIGN

Retrospective review.

SETTING

Academic medical center.

PATIENTS

Forty-five patients diagnosed as having PCP who had direct fluorescent antibody testing for P carinii on either expectorated or induced sputum.

RESULTS

Patients were stratified according to the method of sputum production (induced vs expectorated). The two groups were similar with respect to demographic characteristics, use of prophylaxis with aerosolized pentamidine, serum lactate dehydrogenase level, and arterial oxygen level. When only the initial sputum for each patient was analyzed, there was a similar sensitivity of induced sputum, positive in 10 of 18 samples (56%), and expectorated sputum, positive in 14 of 27 samples (52%) (p>0.05).

CONCLUSION

There was no significant difference in the sensitivity of induced and expectorated sputum for the diagnosis of PCP when the direct fluorescent antibody method of staining was used.

Association of Kaposi's sarcoma associated herpesvirus (KSHV) DNA in bronchoalveolar lavage fluid of HIV infected individuals with bronchoscopically diagnosed tracheobronchial Kaposi's sarcoma

OBJECTIVES

To determine the frequency of detection of Kaposi's sarcoma associated herpesvirus (KSHV), also known as human herpesvirus (HHV) type 8, DNA in bronchoalveolar lavage (BAL) fluid from HIV infected individuals with and without KS and to compare this with the detection rate in peripheral blood. Also to identify whether KSHV was associated with specific cell types in lavage fluid.

METHODS

Nested PCR was used to detect KSHV DNA in BAL fluid from 41 consecutive individuals with Kaposi's sarcoma (KS) and in 41 controls with similar CD4 lymphocyte counts. Semiquantification of viral DNA was by end point titration. A positive cell sorting selection procedure was used to isolate specific BAL fluid cell types.

RESULTS

KSHV DNA was detected in BAL fluid from 24 of 29 (83%) individuals with a bronchoscopic diagnosis of tracheobronchial KS. None was detected in 12 individuals with only cutaneous KS, or in 41 matched controls without KS. In five, KSHV DNA was detected in the cell depleted and cellular fractions of BAL fluid and in 1/5 in the CD14 (macrophage) fractions. None was detected in the CD19 (B lymphocyte) or CD4/CD8 (T lymphocyte) fractions.

CONCLUSIONS

There was a clear association between the diagnosis of tracheobronchial KS and detection of KSHV DNA in BAL fluid. The cell type supporting KSHV in the respiratory tract is not CD 19 positive and has yet to be conclusively identified.

Comparison of induced versus expectorated sputum for diagnosis of pulmonary tuberculosis by acid-fast smear

OBJECTIVE

To evaluate the sensitivity of induced versus expectorated sputum for the diagnosis of pulmonary tuberculosis by acid-fast smear.

METHODS

We performed a retrospective review of data on patients with cultures from respiratory secretions that were positive for Mycobacterium tuberculosis. We analyzed data on the 114 patients with positive cultures during a 4-year period in an urban tertiary care academic medical center.

RESULTS

Sputum samples had been obtained for 103 of the 114 patients with cultures positive for tuberculosis. Forty-four of the 114 patients were HIV seropositive. Overall 33 of 79 patients (42%) had positive acid-fast smears of expectorated sputum, and 6 of 24 (25%) had positive smears of induced sputum (p = 0.21). When data were analyzed for subgroups by HIV serostatus, there was no significant difference in the results. Estimated cost of sputum induction for 1 year was approximately $45,000.

CONCLUSIONS

We found sputum induction to be costly, and induced sputum offered no advantage over routine expectorated sputum for the diagnosis of pulmonary tuberculosis.

Lobar or segmental consolidation on chest radiographs of patients with HIV infection

PURPOSE

To correlate chest radiographic abnormalities with diagnoses in HIV infected patients presenting with acute respiratory symptoms and lobar or segmental consolidation.

MATERIALS AND METHODS

Retrospective review of chest radiographs of 53 HIV infected patients with lobar or segmental consolidation, and their microbiological and cytological diagnoses.

RESULTS

A specific diagnosis was made in 35 patients of which 12 had Pneumocystis carinii pneumonia (including four co-infections) and 23 had bacterial pneumonias (10 of these were due to Streptococcus pneumoniae and four to Mycobacterium tuberculosis). Microbiological and cytological tests were negative in 18 patients. Non-specific radiographic features included bronchial wall thickening (79%), reticulonodular or reticular change (55%), effusions (38%) and lymphadenopathy (25%); effusions favoured a bacterial aetiology. Ten of the 12 cases with P. carinii pneumonia had upper lobe consolidation (three of these had received inhaled pentamadine). Of 13 other cases of upper lobe consolidation, eight were due to pyogenic infection and only one to M. tuberculosis alone.

CONCLUSION

A wide variety of causative agents may produce lobar or segmental consolidation in HIV infected individuals, and the most common cause is bacterial infection. Where there is upper lobe consolidation P. carinii pneumonia should be considered in the differential diagnosis.

CT appearances of intrathoracic Kaposi's sarcoma in patients with AIDS

Although there have been many studies of the plain radiographic appearances of intrathoracic Kaposi's sarcoma in patients with the acquired immunodeficiency syndrome, the computed tomography (CT) findings are less well established. We performed a retrospective review of the thoracic CT findings of 15 patients with tracheobronchial Kaposi's sarcoma diagnosed at bronchoscopy in whom concurrent respiratory infection had been excluded. The commonest CT finding was the presence of ill-defined nodules, seen in all patients. In eight patients more than 20 nodules were seen. Small areas of ground-glass attenuation surrounded one or more nodules in 11 patients. Bilateral perihilar infiltrates were seen in 14 patients, extending into the pulmonary parenchyma along bronchovascular bundles. Interlobular septal thickening was seen in 13 patients and fissural nodularity in 15 patients. To our knowledge this latter finding has not been described before. Discrete areas of ground-glass attenuation were seen in six patients. Small bilateral pleural effusions occurred in six patients; four patients had a pericardial effusion. Shotty mediastinal lymphadenopathy occurred in six patients, and mediastinal nodes greater than 1 cm were present in four patients. None of the patients had CT evidence of chest wall or bone involvement. Although none of these findings are specific, the combination of poorly defined nodules, fissural nodularity and a bronchovascular distribution of perihilar opacities on CT is highly suggestive of pulmonary Kaposi's sarcoma.

Community-based respiratory viral infections in HIV positive patients with lower respiratory tract disease: a prospective bronchoscopic study

OBJECTIVES

To evaluate the contribution of community-based respiratory virus infections to lower respiratory tract disease in HIV-1 infected individuals.

DESIGN

Prospective clinical cohort study.

SETTING

Specialist in-patient unit for HIV and AIDS, University College London Hospitals, London.

SUBJECTS

44 consecutive HIV-1 antibody positive patients who underwent 47 diagnostic bronchoscopies for evaluation of the symptoms and signs of lower respiratory tract disease. TIME: Winter months of 1994/95.

MAIN OUTCOME MEASURES

Detection, in bronchoscopic alveolar lavage fluid, of infection with influenza A and B, respiratory syncytial virus (RSV), parainfluenza 1, 2 and 3 (by immunofluorescence and cell culture) and adenovirus and enteroviruses (by cell culture).

RESULTS

No evidence of influenza, RSV, parainfluenza, adenovirus, or enterovirus infection was detected.

CONCLUSIONS

Despite a marked increase in RSV and influenza B infection in the general population over the winter of 1994-95, respiratory virus infections were not detected in this cohort of HIV infected patients. As the organisms causing lower respiratory tract disease were related to immunosuppression, this study questions the value of routine identification of community-based respiratory viruses in this patient group.

Open lung biopsy for investigation of acute respiratory episodes in patients with HIV infection and AIDS

BACKGROUND

Open lung biopsy (OLB) is rarely necessary for investigation of HIV positive patients with acute respiratory episodes because of the high yield from fibreoptic bronchoscopy with bronchoalveolar lavage (BAL).

METHODS

A retrospective review of OLB in HIV positive patients admitted to a specialist inpatient unit with acute respiratory symptoms was carried out in order to define clinical indications, diagnostic yield, impact on management, complications and outcome.

RESULTS

OLB was performed in 23 patients; 21 had undergone one or more bronchoscopies with BAL (5 also had negative results from transbronchial biopsy). Indications for OLB were: Group A, 15 patients thought clinically to have pneumocystis pneumonia but not responding to treatment; Group B, 4 patients with focal chest radiographic abnormalities; Group C, 4 patients with diffuse radiographic abnormalities and miscellaneous conditions. Preoperative PaO2 (on air) ranged from 4.4 to 14.5 (mean = 9.5) kPa. The results of OLB were in Group A 5 patients had non specific interstitial pneumonitis (NIP), 1 also had Kaposi's sarcoma, 4 had pneumocystis pneumonia (1 also had bronchiolitis obliterans organising pneumonia [BOOP]), 3 had Kaposi's sarcoma and 1 had BOOP and emphysema, 1 had pulmonary infarction and no infection and 1 had normal lung tissue. In Group B diagnoses were NIP, B cell lymphoma, occult alveolar haemorrhage and Pseudomonas aeruginosa pneumonia with BOOP; In Group C 2 patients had NIP and 2 had pneumocystis pneumonia (1 also had cytomegalovirus pneumonitis). All patients survived surgery and none required mechanical ventilation. OLB results significantly affected management; in Group A inappropriate treatment was discontinued in 11 patients found not to have pneumocystis pneumonia, and alternative therapy was begun in the 4 with pneumocystis and in Groups B and C 6 patients began specific therapy; unnecessary therapy was avoided in one and antimicrobial treatment was modified in one.

CONCLUSIONS

Open lung biopsy in HIV positive patients with focal and diffuse radiographic abnormalities has a high diagnostic yield and low morbidity. This investigation should be considered in those with acute respiratory episodes and negative results from bronchoscopic investigations or who have contra-indications to this procedure.

Pneumocystis carinii in bronchoalveolar lavage and induced sputum: detection with a nested polymerase chain reaction

To evaluate polymerase chain reaction (PCR) for detection of Pneumocystis carinii, 117 bronchoalveolar lavage (BAL) specimens, from HIV-infected patients undergoing a diagnostic bronchoscopy, were processed and a nested PCR, followed by Southern blot and hybridization with a P32-labelled probe was performed. The sensitivity and specificity were 85 and 100% 934/40 and 77/77) respectively. A non-radioactive labelling system BluGENE was evaluated on all specimens, and found to be as effective as P32-labelling. To increase the speed and convenience of detection, a dot blot system was tested, but sensitivity dropped markedly with this system. A further 33 patients had both induced sputum and bronchoalveolar lavage performed and the induced sputum was analysed using PCR and routine microbiological methods. The PCR sensitivity on induced sputum was equal to that of routine methods. At present the evaluated PCR cannot replace routine microbiological methods for detection of Pneumocystis carinii, on either BAL fluid or induced sputum.

Efficient diagnosis of Pneumocystis carinii pneumonia

In patients with HIV infection the diagnosis of PCP is relatively simple when patients present late, with advanced pneumonia. The diagnosis becomes more difficult when patients present with minimal symptoms, are receiving specific prophylactic therapy or have had previous AIDS-related pulmonary diseases. A number of non-invasive tests, such as Gallium scanning, exercise-induced hypoxaemia, DTPA scanning and lung function testing have been developed to improve on the diagnostic value of clinical examination and the chest X-ray. Although each has its own particular advantages and disadvantages, the most efficient means of diagnosing PCP, in patients presenting with respiratory symptoms, is to use these investigations as part of a diagnostic algorithm, thereby maximizing resources and defining relative risks for different types of patients.

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

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

Diagnosis of Pneumocystis carinii pneumonia in a population of HIV-positive drug users, with particular reference to sputum induction and fluorescent antibody techniques

Between June 1990 and May 1991, 200 sputum inductions were examined by a fluorescent antibody test (FAT) for Pneumocystis carinii (PC). A total of 164 specimens were negative, 36 were positive and a further 20 inductions were unsuccessful. All patients with a positive result, seven of whom had normal chest X-rays and blood gas analyses, were treated for Pneumocystis carinii pneumonia (PCP) with symptomatic response. Two additional patients were diagnosed as PCP during the study period. No patient with a negative or unsuccessful result developed clinical PCP during that admission, although six did develop 10 episodes of PCP (FAT positive for PC on induced sputum samples) within 3 months of a negative result. Sputum induction was well tolerated by patients and not associated with adverse events. Sensitivity of FAT for PC was 95% and specificity was 100%. These results may in part be because most of the patients were injection drug users (IDUs) who often suffer from chronic productive cough, and also because sputum induction in all cases was supervised by an experienced physiotherapist.

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

BACKGROUND

Respiratory illness is a significant contributor to morbidity and mortality in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome (AIDS). It has been suggested that Pneumocystis carinii pneumonia is no longer the most frequent cause of respiratory disease in this group because of widespread use of prophylaxis and anti-retroviral drugs.

METHODS

A retrospective comparison of the diagnoses in HIV 1 antibody positive patients with respiratory illness admitted to a major UK centre in 1986-7 and 1990-1 was carried out to identify changes in patterns of respiratory disease.

RESULTS

In the 1986-7 period there were 73 patients, of whom none received zidovudine or prophylaxis for pneumocystis pneumonia while in the 1990-1 period there were 122 patients. One hundred and ninety patients (98%) were male homosexuals. Pneumocystis pneumonia remained the commonest respiratory disease, comprising 68% of all diagnoses in the 1986-7 period and 48% in the 1990-1 period. Bacterial infections (bronchitis and pneumonia) were seen more commonly in the 1990-1 period (23%) than in the 1986-7 period (14%), as was pulmonary Kaposi's sarcoma (12% in 1990-1 and 4% in 1986-7). Mycobacterial infection remained uncommon (4% in 1986-7 and 6.5% in 1990-1).

CONCLUSION

Despite widespread use of zidovudine and prophylaxis, pneumocystis pneumonia remains the commonest respiratory disease in homosexual men.

Bronchopulmonary Kaposi's sarcoma in patients with AIDS

BACKGROUND

Kaposi's sarcoma in HIV antibody positive patients may affect the lungs. This study describes the presentation, chest radiographic appearances, and pulmonary function test abnormalities in patients with AIDS who had tracheobronchial Kaposi's sarcoma.

METHODS AND RESULTS

Twenty nine (8%) of 361 consecutive HIV antibody positive patients undergoing bronchoscopy for respiratory symptoms had tracheobronchial Kaposi's sarcoma. Eight patients had intercurrent infections and one had previously received chemotherapy for cutaneous Kaposi's sarcoma; these patients were excluded. Seven of the remaining 20 patients had localised Kaposi's sarcoma (lesions confined to the trachea or the subsegments of one lobe) and 13 had widespread Kaposi's sarcoma (affecting the trachea and one lobe or the subsegments of more than one lobe); 19 patients also had cutaneous and palatal Kaposi's sarcoma. Seven patients, four with widespread disease, had a normal radiograph. All patients had reduced transfer factor (TLCO) and transfer coefficient (KCO) but only those with widespread disease had reductions in forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF). Follow up pulmonary function testing in seven patients (median three months later) showed further reductions in TLCO. All four patients who received no treatment had progressive radiographic abnormalities; bronchoscopy in two patients showed progressive tracheobronchial disease, and two patients had further reductions in FEV1 and FVC. In three patients treated with chemotherapy palliation of symptoms was achieved but two had further reductions in FEV1 and FVC and the radiograph deteriorated. Bronchoscopy showed regression of disease in only one patient.

CONCLUSION

Pulmonary Kaposi's sarcoma produces abnormalities of TLCO even in patients with localised disease; airflow obstruction may occur in patients with widespread disease. Bronchoscopic reassessment of the extent of disease may not accurately reflect response to chemotherapy.

Fulminant bronchopulmonary Kaposi's sarcoma

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An assessment of sputum induction as an aid to diagnosis of respiratory infections in the immunocompromised child

Sputum induction using nebulised hypertonic saline was performed in two groups of immunocompromised children, one group with symptoms of respiratory infection and one group without. The asymptomatic group were bone marrow transplant (BMT) recipients, all seropositive for cytomegalovirus infection (CMV). Organisms were identified in three of 14 induced sputum specimens obtained from the symptomatic group (CMV N = 1, Haemophilus influenzae N = 2), but in none of 12 specimens from the asymptomatic group. Adverse effects encountered were minor. Four symptomatic patients with negative induced sputum samples underwent bronchoalveolar lavage, and no further organisms were identified. Sputum induction can be a useful adjunct to the diagnosis of respiratory pathogens in this group of patients.