An evaluation of symptom and chest radiographic screening in tuberculosis prevalence surveys.

SETTING: A tuberculosis (TB) prevalence survey was performed in 2002 in two urban communities in Cape Town, South Africa. The population was 36,334 in 2001, and the TB notification rate was 341 per 100,000 population for new smear-positive TB in 2002. OBJECTIVE: To evaluate the relative contributions of symptom and chest radiographic (CXR) screening in the detection of subjects with smear- and/or culture-positive TB in prevalence surveys. DESIGN: Information on symptoms, CXR abnormalities, sputum smear and culture was gathered from a random cluster sample of 1170 adults (aged > or = 15 years). Smear and/or culture-positive TB was used as the gold standard. RESULTS: Of 1170 adults, 29 had bacteriologically positive TB (smear- and/or culture-positive). The presence of any abnormalities on CXR had the highest sensitivity for detecting subjects with bacteriologically positive TB (0.97, 95%CI 0.90-1.00). Specificity for any abnormalities on CXR was 0.67 (95%CI 0.64-0.70). The specificity of any of five TB-related symptoms was 0.68 (95%CI 0.65-0.71). Individual symptoms had low sensitivities, ranging from 0.10 for fever to 0.54 for cough of > or = 2 weeks. CONCLUSION: In this TB prevalence survey, CXR screening, but not symptom screening, was a sensitive alternative to sputum examination of all participants.     

Effects of instruction by practice assistants on inhaler technique and respiratory symptoms of patients. A controlled randomized videotaped intervention study

BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.     

Vascular Management During Live Donor Nephrectomy: An Online Survey Among Transplant Surgeons

In 2006, a survey from the American Society of Transplant Surgeons disclosed significant and sometimes fatal hemorrhagic events in live donor nephrectomies (LDN) related to failure of clips, leading to the contraindication of the Weck® Hem‐o‐lok® clip for control of the renal artery during LDN. A survey regarding vascular control techniques, their perceived safety ratings and their failures was sent to 645 European Society for Organ Transplantation members who profiled their profession as “surgeon” and selected “kidney” as organ type. Two hundred forty‐three (41%) members responded, of whom 171 (63.3%) independently perform LDN. Their responses were analyzed. For arterial and venous vascular control, the GIA? and TA?stapler are used most frequently, and were rated the safest. Of the 121 reported hemorrhagic events, slippage and dislodgement of clips occurred at least 58 times, while stapler malfunction occurred at least 40 times. One donor death from hemorrhage related to clip dysfunction was reported. Hemorrhagic complications of LDN with fatal and non‐fatal outcomes still occur. Strikingly, many surgeons do not use the vascular closing technique that they consider most safe. Failure of non‐transfixion techniques is associated with greater risks for the donor. Control of major vessels in LDN must employ transfixion techniques for optimal donor safety.

     

Mutational analysis of the genome-linked protein of cowpea mosaic virus

The coronavirus mouse hepatitis virus (MHV) directs the synthesis of viral RNA on discrete membranous complexes that are distributed throughout the cell cytoplasm. These putative replication complexes are composed of intimately associated but biochemically distinct membrane populations, each of which contains proteins processed from the replicase (gene 1) polyprotein. Specifically, one membrane population contains the gene 1 proteins p65 and p1a-22, while the other contains the gene 1 proteins p28 and helicase, as well as the structural nucleocapsid (N) protein and newly synthesized viral RNA. In this study, immunofluorescence confocal microscopy was used to define the relationship of the membrane populations comprising the putative replication complexes at different times of infection in MHV-A59-infected delayed brain tumor cells. At 5.5 h postinfection (p.i.) the membranes containing N and helicase colocalized with the membranes containing p1a-22/p65 at foci distinct from sites of M accumulation. By 8 to 12 h p.i., however, the membranes containing helicase and N had a predominantly perinuclear distribution and colocalized with M. In contrast, the p1a-22/p65-containing membranes retained a peripheral, punctate distribution at all times of infection and did not colocalize with M. By late times of infection, helicase, N, and M each also colocalized with ERGIC p53, a specific marker for the endoplasmic reticulum-Golgi-intermediate compartment. These data demonstrated that the putative replication complexes separated into component membranes that relocalized during the course of infection. These results suggest that the membrane populations within the MHV replication complex serve distinct functions both in RNA synthesis and in delivery of replication products to sites of virus assembly.     

Tuberculosis culture testing at a tertiary care hospital: options for improved management and use for treatment decisions.

SETTING: Chris Hani Baragwanath Hospital, a tertiary care hospital in Johannesburg, South Africa. OBJECTIVES: To determine the proportion of patients with positive Mycobacterium tuberculosis cultures and whether those who were positive were on treatment. DESIGN: Tuberculosis (TB) culture results were obtained from the laboratory for a 3-month period. Positive results were checked against registrations at the hospital TB Care Centre (TBCC). The treatment status of non-registered patients was obtained from various records at the hospital, district clinics and from home visits. RESULTS: Overall, 3909 patients had 5404 samples sent for culture. Of these, 708 patients (18%) had at least one positive culture. The positive yield from 2749 adult sputum samples was 33% and ranged from 6% to 40% for different extra-pulmonary specimens. Among 1160 children, the yield varied from 0% to 12%, with 12% in sputum and gastric washing specimens. Of the 708 culture-positive patients, 429 (61%) patients were registered at the TBCC and were known to have started TB treatment. Of the 279 subjects not registered (39% overall), 100 (36%) died. Only 67 of the 179 survivors were confirmed on treatment, 40 were not on treatment and 72 could not be traced. CONCLUSIONS: Large numbers of TB culture tests were performed, some inappropriately. Study findings highlight inadequacies in the management of culture-confirmed TB at this hospital.     

The epidemiology of tuberculosis among asylum seekers in The Netherlands: implications for screening.

OBJECTIVE: To identify low-risk groups among asylum seekers in the Netherlands that may be excluded from tuberculosis (TB) screening at entry or during follow-up. METHODS: A retrospective cohort study of medical records of asylum seekers entering the country between January 1994 and March 1997. RESULTS: Medical records were available for 46,424 of the 96,000 asylum seekers (48%) in this period. One hundred and three pulmonary TB cases were diagnosed at entry (prevalence 222/100,000). Risk factors were age >11 years, history of imprisonment and country of origin at war or with TB incidence >100/100,000. During a mean follow-up period of 10 months, 51 pulmonary TB cases were diagnosed (incidence 134/100,000 person-years). Risk factors were age >11 years, old lesions on entry X-ray, and country of origin whose asylum seekers had a prevalence of TB at entry >200/100,000. CONCLUSIONS: We conclude that 1) those with abnormal X-ray at entry should receive preventive therapy after exclusion of active TB, or undergo intensive follow-up, 2) periodic screening is not indicated for immigrants from countries whose asylum seekers have a low prevalence of pulmonary TB at entry, and 3) children <12 years can be excluded from screening.     

High prevalence of tuberculosis in previously treated patients, Cape Town, South Africa

The tuberculosis (TB) notification rate is high and increasing in 2 communities in Cape Town, South Africa. In 2002, we conducted a prevalence survey among adults > or = 15 years of age to determine the TB prevalence rate; 15% of households in these communities were randomly sampled. All persons living in sampled households were eligible for chest radiography and sputum examination. Of the 3,483 adults who completed a questionnaire, 2,608 underwent chest radiography and sputum examination. We detected 26 bacteriologically confirmed TB cases and a prevalence of 10.0/1,000 (95% confidence interval [CI] 6.2-13.8 per 1,000). We found 18 patients with smear-positive TB, of whom 8 were new patients (3.1/1,000, 95% CI 0.9-5.1/1,000). More than half of patients with smear-positive TB (10, 56%) had previously been treated. Such patients may contribute to transmission of Mycobacterium tuberculosis and the high TB prevalence rate. Successful treatment of TB patients must be a priority.     

Proportion of tuberculosis transmission that takes place in households in a high-incidence area

The prevalence of infection among household contacts of people with tuberculosis is high. This information frequently guides active case finding. We analysed DNA fingerprints of Mycobacterium tuberculosis from 765 tuberculosis patients in Ravensmead and Uitsig, adjacent suburbs of Cape Town, South Africa. In 129 households in which DNA fingerprints were available for more than one patient, we identified 313 patients, of whom 145 (46%) had a fingerprint pattern matching that of another member of the household. The proportion of transmission in the community that took place in the household was 19%, and therefore, in this high-incidence area, tuberculosis transmission occurs mainly outside the household.