Chronic cough in patients with HIV infection

Perspectives on neuroinflammation contributing to chronic cough

Chronic cough can be a troublesome clinical problem. Current thinking is that increased activity and/or enhanced sensitivity of the peripheral and central neural pathways mediates chronic cough via processes similar to those associated with the development of chronic pain. While inflammation is widely thought to be involved in the development of chronic cough, the true mechanisms causing altered neural activity and sensitisation remain largely unknown. In this back-to-basics perspective article we explore evidence that inflammation in chronic cough may, at least in part, involve neuroinflammation orchestrated by glial cells of the nervous system. We summarise the extensive evidence for the role of both peripheral and central glial cells in chronic pain, and hypothesise that the commonalities between pain and cough pathogenesis and clinical presentation warrant investigations into the neuroinflammatory mechanisms that contribute to chronic cough. We open the debate that glial cells may represent an underappreciated therapeutic target for controlling troublesome cough in disease.

Respiratory Complications in Iranian Hospitalized Patients with HIV/AIDS

Background

The respiratory tract has been the most commonly affected site of illness in HIV-infected patients. The current study was done to identify the frequency of respiratory complications in a consecutive case series of HIV-positive patients in Iran.

Materials and Methods

This study was a retrospective analysis at the national academic reference medical center of Imam-Khomeini Hospital, in Tehran, Iran. The study included 199 new admissions for 177 HIV-infected patients between 2000 and 2005. Demographic characteristics, risk factors for HIV infection, respiratory complications, and CD4+ lymphocyte counts were evaluated in these patients.

Results

All patients were males. The mean age was 35 years (age range: 15 to 63 years). Among 34 cases with available CD4+ lymphocyte count results, 70.6% had results <200 cells/mm³. Nearly half the patients (47.7%) had respiratory symptoms. The most common pulmonary complications were cough (86.3%), sputum (71.6%), dyspnea (54.7%), and hemoptysis (10.5%). The most common diagnosis was pulmonary tuberculosis (27.1%), followed by other bacterial pneumonias (16.6%) and pneumocystis carinii pneumonia (4.5%). Intravenous drug users who had history of incarceration had the highest risk factors for Mycobacterium tuberculosis infection (59%), and other bacterial pneumonias (52%).

Conclusion

Our study demonstrates that respiratory complications are highly frequent in HIV patients in Iran and that pulmonary tuberculosis is still a common complication in HIV infected patients, despite the availability of effective treatment. Results suggest the need for more effective preventive and prophylactic measures, wider use of antiretroviral treatment and effective chemotherapy for Iranian patients with HIV/AIDS.

Control of antibiotic use by a unit-dose drug distribution system

The aim of the study was to test a new model of drug distribution known as unit-dose drug distribution including the effects of implementing this system on total drug consumption, especially in curbing antimicrobial use.

The study was carried out in the Department of Surgery at the University Clinical Center in Nis, Serbia. During the first six months of the study (comparative period), drugs were delivered directly from the pharmacy to the urology and orthopedic wards in the traditional way (ward stock system). During the next six months (study period), drugs were delivered directly from the pharmacy to the patients (unit-dose drug distribution system). Drug consumption was measured using the statistical unit defined daily dose (DDD) per 100 bed days according to the anatomical-therapeutic-chemical classification of drugs. Following implementation of the unit-dose drug distribution system, total drug consumption was reduced by 24.34% in the urology ward and by 21.43% in the orthopedic ward. During the comparative period, in the urology and orthopedic wards, systemic antiinfectives (group J) comprised 263.54 and 227.61 DDD/100 bed days or 43.05% and 25.52% of total drug consumption respectively, whereas, during the pilot study period this group of drugs comprised 191.63 and 173.52 DDD/100 bed days or 41.37% and 24.96% of total drug consumption respectively.

The unit-dose distribution system of drugs in hospitals leads to a control of drug consumption and substantial savings. Also, the pharmacist-physician interaction began to emerge as an important factor as a direct result of the changes in the drug distribution system.

Cough in the immunocompromised host: ACCP evidence-based clinical practice guidelines

BACKGROUND

Patients with compromised immune systems often complain of chronic cough. While these patients are susceptible to opportunistic infections that should be considered in the evaluation, common causes should also be investigated.

METHODS

MEDLINE search using the terms "cough," "immunocompromise," "HIV," "AIDS," "neutropenia," and "corticosteroids," from 1966 through the end of 2003.

RESULTS

Patients with compromised immune systems and chronic cough usually have the same disorders causing cough as in the general population. However, depending on the nature and severity of the immune defect, they may also have a variety of infections not usually encountered in immunocompetent hosts.

CONCLUSION

In immunocompromised patients presenting with cough, the initial diagnostic evaluation should be the same as that for healthy hosts. However, when these diagnoses have been excluded, opportunistic infections should be considered.

Future Directions in the Clinical Management of Cough

OBJECTIVES

To impart a call for further research into the identified domains of particular interest in the etiology, management, and treatment of cough.

DESIGN/METHODOLOGY

A literature review was performed using the search term "cough" in PubMed between 1983 and 2004. The final draft of this guideline was reviewed, in addition to recent studies on cough, and suggestions provided by the authors were collated into a definitive inventory of specific areas in which the lack of quality evidence encumbered the development of clinically relevant evidence-based recommendations.

RESULTS/CONCLUSIONS

Although our understanding of the causes and optimal management of chronic cough have significantly increased over the past 25 years, further research remains to be done on this common symptom. This is reflected by the generally low level of evidence for many of the recommendations in these guidelines. Research is particularly needed on the optimal treatment of postinfectious cough, how to distinguish acute bronchitis from other conditions, how to reliably diagnose and treat cough due to gastroesophageal reflux disease, clearly identifying a role for nonpharmacologic protussive treatment modalities in diseases associated with an increased production of bronchial secretions, determining how often cough in patients with interstitial lung disease is due to conditions other than these, establishing the spectrum and frequency of causes of chronic cough in the immunocompromised hosts, and better characterizing psychogenic cough. Further studies are also needed on methods for the assessment of cough, in particular, noninvasive measures of airway inflammation, and pharmacotherapy. It should be determined how often unexplained cough (previously referred to as idiopathic cough) is due to the use of non-evidence-based guidelines or to environmental causes, and assessed whether an empiric, integrative approach of diagnosing chronic cough leads to better outcomes, including cost-effectiveness, than routine testing. While much work has been done on chronic cough, we need studies on the spectrum and frequency of acute and subacute coughs.

Circulating antibodies to lipoarabinomannan in relation to sputum microscopy, clinical features and urinary anti-lipoarabinomannan detection in pulmonary tuberculosis

An enzyme-linked immunosorbent assay (ELISA)-based investigation of anti-lipoarabinomannan (LAM) antibody levels in the sera of patients with acid-fast bacilli (AFB)-positive pulmonary tuberculosis (PTB), AFB-negative PTB and non-TB respiratory tract symptoms was conducted. The anti-LAM results were further evaluated using urine LAM detection and a clinical diagnostic score (DS) system as references. Using sputum AFB as a reference, positive anti-LAM was found in 66.9% of 139 AFB-positive PTB, 34.4% of 61 AFB-negative PTB and 23.5% of 800 non-TB patients and in 8% of 50 healthy individuals. The positive and negative predictive values were 48.7% and 87.4%, respectively. Using the DS as a reference, the sensitivity and specificity were 50.5% and 78.3%, respectively, whereas 45.8% of urine LAM positives and 77.9% of urine LAM negatives were correctly identified by the anti-LAM ELISA. In TB endemic areas a negative anti-LAM could be of practical value, particularly when other indicators of PTB are negative. Using any of these methods as a reference, a positive anti-LAM would mislead in about one-quarter of cases. Had all the 3 methods been combined and at least 2 positive tests sufficed, 90.6% of AFB-positive PTB, 52.5% of AFB-negative PTB and 94.9% of non-TB patients would have been correctly diagnosed. Apart from the possible impact of HIV, the low accuracy of the current assay could be due to intravascular formation of LAM-anti-LAM complexes, latent TB or environmental mycobacterial infections.