Host Risk Factors for Tuberculosis.

Tuberculosis (TB) spreads through droplets that contain Mycobacterium tuberculosis (Mtb) and can infect susceptible people. Due to different risk factors, people have different susceptibility ranges towards TB. The risk factors are classified into three main groups, includ-ing bacterial, environmental, and host factors. Literature review reveals that the most important host risk factors are aging, male gender, genetics, epigenetics, having an impaired immune system, diabetes, malignancy, malnutrition, anemia, and pregnancy. The risk factors contribute to the increase in TB cases through inflammation, increased contact with TB patients, disrup-tion of immune genes, changes in gene expression, increased activity of Mtb, damage to cellu-lar immunity, reactivation of Latent TB Infection (LTBI), increased susceptibility to TB, com-promised immunity, and changes in the proportion of T cell subgroups, respectively. Therefore, identification of the infection source and high-risk people and timely treatment of the patients can reduce TB mortality and help control the disease.

Neurocognitive impairment after off-pump and on-pump coronary artery bypass graft surgery - an Iranian experience.

BACKGROUND: Coronary artery bypass graft (CABG) surgery is one of the most commonly performed surgical procedures worldwide, and it may be accompanied by postoperative neurocognitive impairment. Although this complication has been attributed to the use of cardiopulmonary bypass, it is still a matter of debate whether the switch from on-pump to off-pump technique affects the cognitive function. OBJECTIVE: The aim of this study was to compare the impact of the on-pump and off-pump techniques on neurocognitive impairment in low-risk CABG surgery groups. METHODS: In a descriptive and analytic study, 201 CABG patients with left-ventricular ejection fraction >30%, and without cardiac arrhythmia were enrolled. Before the elective operation, all patients underwent neurological examination and neurocognitive test, Mini-Mental State Examination (MMSE). Two months following the operation, both on- and off-pump, the patients were re-examined by MMSE to detect any neurocognitive impairment. RESULTS: Out of 154 patients included in the study, 95 (61.6%) and 59 (38.3%) patients were in off-pump and on-pump groups, respectively. Mean age of the patients was 57.17 ± 9.82 years. A 2-month postoperative neurocognitive impairment was detected among 17 patients of on-pump group (28.8%) and in 28 cases of off-pump group (29.4%) (P = 0.54). The mean postoperative MMSE scores were not comparable between groups (25.01 ± 4.49 in off-pump group versus 23.73 ± 4.88 in on-pump group, P = 0.09). CONCLUSION: The present study revealed that in low-risk patients undergoing CABG surgery, either the techniques of on-pump or off-pump did not differ regarding the neurocognitive outcome 2 months after the procedure.

Mediastinitis after cardiac surgery in Madani Heart Center, Tabriz, Iran.

Post-sternotomy infections are a kind of nosocomial infection involving the mediastinum space and the sternum, with a high morbidity and mortality rate. The present study was carried out to identify the incidence of mediastinitis following cardiac surgery and the most common risk factors. Cardic patients undergoing surgery were studied for suspicious mediastinitis infection at the Madani Heart Center, Tabriz, Iran from 2004 to 2006. The most common isolated agents included the coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa and Enterobacter spp. Incidence of postoperative mediastinitis after cardiac surgery was 1.2%. The mortality rate of postoperative mediastinitis was high (34.3%). Wound infection, especially mediastinitis following cardiac surgery, is rare but could be life-threatening. The most important step in the management of wound infections is prevention, and preventive measures could be strengthened by identifying the risk factors.