Use of induced sputum specimens for microbiologic diagnosis of infections due to organisms other than Pneumocystis carinii

Melioidosis: A Fulminant Infection in a Patient with Uncontrolled Diabetes

Melioidosis is an endemic infection in Southeast Asia and Northern Australia commonly manifesting with pneumonia and localized skin infection. Though most exposures do not lead to severe illness, a fulminant infection can occur among patients with risk factors. A 59-year-old male presented with cough with expectoration and fever for 1 week. He had diabetes for 10 years with poorly controlled blood sugars. Contrast-enhanced computerized tomography (CECT) of thorax showed right upper lobe consolidation with diffuse ground-glass opacities in right upper lobe along with microabscesses in liver and spleen. Sputum culture and Xpert mycobacterium tuberculosis complex and resistance to rifampin (MTB/RIF) for tuberculosis were negative. Bronchoalveolar lavage culture grew Burkholderia pseudomallei. He was treated with initial intensive therapy with injection amoxicillin-clavulanic acid for 2 weeks and subsequently started on eradication therapy with tablet trimethoprim-sulfamethoxazole. Diagnosis of melioidosis should be considered in a patient of pneumonia with multiorgan involvement in an endemic area, especially with underlying risk factors.

Nontuberculous mycobacterial pulmonary disease diagnosed by two methods: a prospective cohort study

Background

Microbiological criteria for diagnosing nontuberculous mycobacterial pulmonary disease (NTM-PD) include positive culture results from at least two separately expectorated sputum specimens or one bronchial washing or lavage. However, the clinical similarities and differences between patients diagnosed by these two methods remain unclear. We compared clinical features and prognoses of patients with NTM-PD diagnosed from both specimen types.

Methods

We analysed data from patients who participated in the Seoul National University Hospital NTM-PD cohort (ClinicalTrials.gov identifier: NCT01616745). Baseline demographics, symptoms, radiographic findings, disease progression, and treatment responses were summarized and compared between patients diagnosed from sputum specimens and patients diagnosed from bronchoscopic specimens.

Results

Three hundred forty-seven patients were included in the analyses. Of these, 279 (80.4%) were diagnosed from two separately expectorated sputum specimens, and 68 (19.6%) were diagnosed from bronchoscopic specimens. Patients diagnosed from sputum specimens had more frequent and severe cough, sputum, postnasal drip, and high St. George’s Respiratory Questionnaire scores. However, the extent and severity of the radiographic lesions, disease progression, and treatment responses were similar for both groups. Further analysis based on the following three groups (sputum culture positive, sputum culture negative/bronchoscopy, and scanty sputum/bronchoscopy groups) suggested that the scanty sputum/bronchoscopy group appeared to have the worst prognosis in terms of both time to progression and time to culture conversion.

Conclusions

Although some symptoms and quality of life were worse in patients with NTM-PD diagnosed from sputum specimens, their prognoses were similar to those of patients diagnosed by bronchoscopic specimen. We recommend bronchoscopic sampling for patients in whom NTM-PD is suspected clinically or radiographically, especially those who have no or scanty sputum.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4078-0) contains supplementary material, which is available to authorized users.

Committee II: Guidelines for cytologic sampling techniques of lung and mediastinal lymph nodes

The Papanicolaou Society of Cytopathology has developed a set of guidelines for pulmonary cytology including indications for bronchial brushings, washings, and endobronchial ultrasound guided transbronchial fine-needle aspiration (EBUS-TBNA), technical recommendations for cytological sampling, recommended terminology and classification schemes, recommendations for ancillary testing and recommendations for post-cytological management and follow-up. All recommendations are based on the expertise of the authors, an extensive literature review and feedback from presentations at national and international conferences. This document selectively presents the results of these discussions. The present document summarizes recommendations regarding techniques used to obtain cytological and small histologic specimens from the lung and mediastinal lymph nodes including rapid on-site evaluation (ROSE), and the triage of specimens for immunocytochemical and molecular studies.

Management of community-acquired pneumonia in immunocompetent adults: updated Swedish guidelines 2017

Based on expert group work, Swedish recommendations for the management of community-acquired pneumonia in adults are here updated. The management of sepsis-induced hypotension is addressed in detail, including monitoring and parenteral therapy. The importance of respiratory support in cases of acute respiratory failure is emphasized. Treatment with high-flow oxygen and non-invasive ventilation is recommended. The use of statins or steroids in general therapy is not found to be fully supported by evidence. In the management of pleural infection, new data show favourable effects of tissue plasminogen activator and deoxyribonuclease installation. Detailed recommendations for the vaccination of risk groups are afforded.

Pneumonia in Trauma Patients

Purpose of Review

This article reviews the new definitions of pneumonia, discusses risk factors for pneumonia among trauma patients, presents the latest evidence for prevention strategies, discusses the best ways to make the diagnosis, and reviews the microbiology and treatment for trauma patients with pneumonia.

Recent Findings

Pneumonia can be prevented by decreasing the duration of mechanical ventilation using daily paired spontaneous awakening and breathing trials, but not with early tracheostomy placement. Other useful prevention strategies include semirecumbent positioning and oral care. Mini-BAL is a sensitive and specific means of securing the diagnosis of pneumonia that does not require a physician to be present and is therefore especially useful in busy trauma centers.

Summary

Pneumonia is a frequent complication among trauma patients. Risk factors are largely unmodifiable. However, trauma centers can institute routine daily paired spontaneous awakening and breathing trials to decrease the duration of ventilation and incidence of pneumonia. Future research is needed to further characterize the microbiology of pneumonia among trauma patients.

Lower Respiratory Tract Infections

This review will focus on the infectious etiologies and more common noninfectious causes of lower respiratory tract syndromes among major immunosuppressed populations. The changing epidemiology of infections in the era of highly active antiretroviral therapy (HAART) in the case of HIV-positive patients and the impacts of both newer immune-suppressant therapies and anti-infective prophylaxis for other immunocompromised hosts will be discussed, with emphasis on diagnostic approaches and practice algorithms.

Swedish guidelines on the management of community-acquired pneumonia in immunocompetent adults--Swedish Society of Infectious Diseases 2012

This document presents the 2012 evidence based guidelines of the Swedish Society of Infectious Diseases for the in- hospital management of adult immunocompetent patients with community-acquired pneumonia (CAP). The prognostic score 'CRB-65' is recommended for the initial assessment of all CAP patients, and should be regarded as an aid for decision-making concerning the level of care required, microbiological investigation, and antibiotic treatment. Due to the favourable antibiotic resistance situation in Sweden, an initial narrow-spectrum antibiotic treatment primarily directed at Streptococcus pneumoniae is recommended in most situations. The recommended treatment for patients with severe CAP (CRB-65 score 2) is penicillin G in most situations. In critically ill patients (CRB-65 score 3-4), combination therapy with cefotaxime/macrolide or penicillin G/fluoroquinolone is recommended. A thorough microbiological investigation should be undertaken in all patients, including blood cultures, respiratory tract sampling, and urine antigens, with the addition of extensive sampling for more uncommon respiratory pathogens in the case of severe disease. Recommended measures for the prevention of CAP include vaccination for influenza and pneumococci, as well as smoking cessation.

α1,3-galactosyltransferase deficiency in germ-free miniature pigs increases N-glycolylneuraminic acids as the xenoantigenic determinant in pig-human xenotransplantation

In this study, we examined whether Hanganutziu-Deicher (H-D) antigens are important as an immunogenic non-α1,3-galactose (Gal) epitope in pigs with a disrupted α1,3-galactosyltransferase gene. The targeting efficiency of the AO blood genotype was achieved (2.2%) in pig fibroblast cells. A total of 1800 somatic cell nuclear transfer (SCNT) embryos were transferred to 10 recipients. One recipient developed to term and naturally delivered two piglets. The α1,3-galactosyltransferase activity in lung, liver, spleen, and testis of heterozygote α1,3-galactosyltransferase gene knockout (GalT-KO) pigs was significantly decreased, whereas brain and heart showed very low decreasing levels of α1,3-galactosyltransferase activity when compared to those of control. Enzyme-linked lectinosorbent assay showed that the heterozygote GalT-KO pig had more sialylα2,6- and sialylα2,3-linked glycan than the control. Furthermore, the heart, liver, and kidney of the heterozygote GalT-KO pig had a higher N-glycolylneuraminic acid (Neu5Gc) content than the control, whereas the lung of the heterozygote GalT-KO pig had Neu5Gc content similar to the control. Collectively, the data strongly indicated that Neu5Gc is a more critical xenoantigen to overcoming the next acute immune rejection in pig to human xenotransplantation.

Microbiological diagnostic procedures in respiratory infections: suppurative lung disease

Pursuing a microbiological diagnosis in suppurative lung disease can enable focused antibiotic therapy, identify pathogens of potential concern for infection control, and in some cases delineate a specific pathological process. Suppurative lung disease can be categorized as acute or chronic. Acute disease most commonly consists of lung abscess or parapneumonic empyema. The vast majority of chronic suppurative lung disease in childhood is due to cystic fibrosis. Samples from the respiratory tract offer the most useful information for diagnosis and management, but adjunctive information can also be obtained from serological methods, blood cultures and molecular techniques. The quality of respiratory tract samples is vital to aid accurate interpretation of results, and this varies according to the technique of collection. Antibiotic sensitivity testing is of particular importance in an era of evolving antibiotic resistance and can be problematical in cystic fibrosis.

Swedish guidelines for the management of community-acquired pneumonia in immunocompetent adults

This document presents the evidence-based guidelines of the Swedish Society of Infectious Diseases for the management of adult immunocompetent patients with community-acquired pneumonia (CAP), who are assessed at hospital. The prognostic score 'CURB-65' is recommended for all CAP patients in the emergency room. The score provides an assessment tool for the decision regarding outpatient treatment or level of hospital supervision, the choice of microbiological investigations, and empirical antibiotic treatment. In patients with non-severe CAP (CURB-65 score 0-2) we recommend initial narrow-spectrum antibiotic treatment, orally or intravenously, primarily directed at Streptococcus pneumoniae. In those with CURB-65 score 3, penicillin G or a cephalosporin intravenously is recommended. For CURB-65 score 0-3 atypical pathogens should be covered only when they are suspected on clinical or epidemiological grounds. In patients with CURB-65 score 4-5 intravenous combination therapy with either cephalosporin/macrolide or penicillin G/fluoroquinolone is recommended. Efforts should be made to identify the CAP aetiology in order to support the ongoing antibiotic treatment or to suggest treatment alterations. Recommended measures for prevention of CAP include influenza -- and pneumococcal -- vaccination to risk groups and efforts for smoking cessation.

The role of induced sputum in the diagnosis of pulmonary tuberculosis

OBJECTIVES

To determine the sensitivity of referral guidelines for induced sputum in pulmonary tuberculosis (PTB) case detection and determine the diagnostic yield of the test.

METHODS

A retrospective analysis of case notes of adult patients referred for induced sputum was carried out at the North Trent Regional Department of Infection and Tropical Medicine, the Royal Hallamshire Hospital, Sheffield, UK. Clinical characteristics were noted on patients referred during a 12-month period in 2001-2002, and of all patients with positive induced sputum results from April 1998 to March 2002.

RESULTS

Over a 12-month period 114 patients were referred in our unit for induced sputum sampling. Twelve of the 114 patients had positive sputum cultures giving a positive yield for the test of 10.5%. With strict adherence to our referral guidelines, 10 of the 12 positive cases (83.3%) would have been detected. With modification to the referral guidelines, all 12 microbiologically positive cases would have been detected making the guidelines 100% sensitive in detecting microbiologically positive cases among patients referred with a clinical suspicion of PTB who are unable to self-expectorate. The positive yield for the test would have been increased to 13.2%. In the past 4 years 29 patients had positive induced sputum results. Of these, 11 patients (37.9%) had concurrent microbiological proven extra-pulmonary TB (EPTB) and 10 (34.5%) had past histories of TB infection. Seven patients had chest X-rays reported as normal.

CONCLUSIONS

Induced sputum offers a relatively non-invasive investigation for patients with suspected PTB who are unable to bring up sputum. Induced sputum also offers a means of establishing a microbiological diagnosis in some cases of EPTB. An investigative algorithm is suggested.Summary. In an era of increasing drug resistant disease, establishing a microbiological diagnosis of TB is paramount. Sputum induction can be used as an alternative investigation to bronchoscopy in suspected PTB patients who are able to self-expectorate. Induced sputum is a sensitive investigation for suspected PTB patients but with a low diagnostic yield. Referral guidelines are suggested.

Induced sputum and bronchoscopy in the diagnosis of pulmonary tuberculosis

BACKGROUND

Previous studies suggest that bronchoscopy and a single induced sputum sample are equally effective for diagnosing pulmonary tuberculosis.

METHODS

In a prospective study of subjects with possibly active pulmonary tuberculosis, the diagnostic yield of three induced sputum tests was compared with that of bronchoscopy. Subjects either produced no sputum or (acid fast) smear negative sputum. Bronchoscopy was only performed if at least two induced sputum samples were smear negative.

RESULTS

Of 129 subjects who completed all tests, 27 (21%) had smear negative and culture positive specimens, 14 (52%) on bronchoscopy and 26 (96%) on induced sputum (p<0.005). One patient was culture positive on bronchoscopy alone compared with 13 on induced sputum alone; 13 were culture positive on both tests. Induced sputum positivity was strikingly more prevalent when chest radiographic appearances showed any features of active tuberculosis (20/63, 32%) than when appearances suggested inactivity (1/44, 2%; p<0.005). Induced sputum costs were about one third those of bronchoscopy, and the ratio of costs of the two tests per case of tuberculosis diagnosed could be as much as 1:6.

CONCLUSIONS

In subjects investigated for possibly active or inactive tuberculosis who produce no sputum or have smear negative sputum, the most cost effective strategy is to perform three induced sputum tests without bronchoscopy. Induced sputum testing carries a high risk of nosocomial tuberculosis unless performed in respiratory isolation conditions. The cost benefits shown could be lost if risk management measures are not observed.

Laboratory diagnosis of community-acquired lower respiratory tract infection

This article has focused on the evaluation of outpatients with lower respiratory illness. In large part, the need for microbiological work-up is host-dependent. Healthy patients usually do well, and laboratory data are often unnecessary. The abnormal host requires a different approach and, in general, the more compromised the host, the more aggressive the laboratory evaluation. A renal transplant patient with respiratory symptoms often follows the dictum that "common things happen commonly;" however, the clinician needs that extra level of assurance in this case. Some transplant patients may have respiratory illness caused by strongyloidiasis. Cystic fibrosis is another example of the need for a more comprehensive laboratory evaluation. Specialized selective media and additional susceptibility studies may be needed to evaluate isolates associated with exacerbation of symptoms in these patients. The clinical laboratory should be forewarned of any materials coming from invasive diagnostic techniques, so they can prepare and offer useful advice regarding specimens, transport, and follow-up. Microbiological laboratories are often most knowledgeable regarding what type of testing is appropriate. Direct communication with the laboratory is essential to assure the best patient care.

Airway inflammation in children with cystic fibrosis and healthy children assessed by sputum induction

A noninvasive method to characterize inflammation and infection in the airways of nonexpectorating children with cystic fibrosis (CF) is needed for clinical and research purposes. Accordingly, we performed sputum inductions by administering 3% saline to 11 healthy control children and 20 children with CF, composed of 7 sputum producers (capable of spontaneously expectorating sputum) and 13 nonproducers. Induced sputum weights were comparable in each group, whereas the amount of induced sputum collected from the CF producers was over 10-fold higher than the spontaneously expectorated samples. We found a significant increase in indices of airway inflammation, including total cell counts, absolute neutrophil counts, interleukin-8 (IL-8) levels, and neutrophil elastase activity in the CF subjects compared with the healthy control subjects. These same indices in the induced sputum specimens from CF producers were significantly correlated with levels in the matched expectorated sputum specimens. Sputum total protein concentration was elevated in the CF groups, whereas urea and albumin levels were not significantly different. Salivary analysis, performed separately, revealed higher levels of IL-8 and total protein in the CF groups. Airway infection, as assessed by quantitative counts of CF-related bacterial pathogens, was also higher in the CF subjects. The same bacterial pathogens, in similar colony counts, were isolated from both the induced and expectorated sputum samples from the CF producers. We conclude that airway inflammation and infection, assessed through sputum induction, are significantly increased in children with CF as compared with healthy children. Furthermore, induced sputum samples are similar to spontaneously expectorated samples in describing both inflammation and infection in the CF airway.

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.

Value of noninvasive studies in community-acquired pneumonia

Noninvasive diagnostic studies, i.e., sputum gram stain, sputum culture, blood culture and antigen detection assays will assist the clinician in the selection of initial antimicrobial therapy in some patients. These tests may be even more valuable in adjusting treatment regimens to prevent the use of broad spectrum antimicrobial agents as routine therapy.

Fever in patients with HIV infection

Fever is a common sign during the course of HIV infection, usually represents a superimposed opportunistic infection, and is almost always a treatable condition. Proper management generally requires detection of the underlying cause, and the diagnostic evaluation is largely driven by the clinical symptoms, associated conditions such as injection drug use, and stage of disease based largely on the absolute CD4 cell count. This article provides guidelines for the management of fever in the patient with HIV infection.