Tehran University Medical Journal

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Yersinia enterocolitis causes a wide spectrum of human diseases including gasteroentritis, which is the most frequent of its manifestation. Other diseases and clinical syndromes resulting from Yersinia enterocolitica are septicemia, mesenteric lymphadenitis, apendisitis, exudative pharyngitis, reactive artiritis, nodosum erythema and rarely Reiter's syndrome. In many countries such as western European, Scandinavian and north American countries, Australia and Japan the role of Yersinia enterocolitica particularly the 0:3, 0:8 and 0:9 serotypes in human diseases have been clearly identified. In spite of significant development in the field of separating Yersinia enterocolitica from feces as well as from the environmental specimens during the last decade, there has been only one documented report of isolating Yersinia enterocolitica in Iran in 1977. Thus we decided to test 300 samples of feces within 5 months. In this method, CIN agar as a selective and special medium and Mac conkey agar as classic medium were used. Also cold enrichment method in PBS (pH=7.8) was used. In order to determine importance of enterocolitica, we separated other pathogens of intestine such as salmonella, shigella and entropathogenic E.Coli. The achieved results from abundance points of view are as follows: 17 strains of EPEC (5.66%), 9 strains of shigella (3%), 8 strains of Yersinia enterocolitica (2.66%) and 6 strains of salmonella (2%)

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Post partum haemorrhage (PPH) and retained placenta are the most common serious abnormalities encountered during the third stage of labour. PPH is one of the most common causes of mortality in childbirth, particularly in developing countries. The incidences of PPH and retained placenta have decreased with the use of synthetic oxytocin and controlled cord traction (CCT). Weather such treatment is valuable is open to question because of the lack of clinical and physiological studies. Unfortunately, oxytocic drugs are not available to about half the women of developing countries, who do not deliver under the care of a trained midwife. We know that sucking stimulates uterine contractions in lactating women. This effect is probably mediated by the high plasma oxytocin levels that occur during preparations for breast-feeding and again within 3 min of the start of sucking. Traditional birth attendants (TBAs) do not have the skill to administer injectable oxytoxics. It has become the practice in some TBA training programmes to teach that the risk of PPH can be reduced if the mother puts her baby to the breast immediately after delivery. Objective: To determine the effect of sucking immediately after childbirth on the length of 3rh stage and amount of bleeding in the first day. This is a semi-experimental study. It was done in Tehran'e Mirzakochak hospital. 100 women received oxytocin intramuscularly and 120 women were placed in sucking group. Then the lenghth of 3rd stage and amount of bleeding in the first day was compared between two groups. Results: The duration of the third stage and number of pads different between oxytocin group and sucking group (4.42 vs 6.08 min) and (10.58 vs 11.72 number). As for the, parity, gestational age, maternal systolic and diastolic blood pressure, infant weight and hight, the results showed no significant difference between the groups. As for the, maternal age, the results showed differed significantly between the groups. As for the gestational age, the results of the research showed that between the gestational age and the duration of the third stage, there was a reverse correlation in multipare women. So when gestational age decreases the duration of third stage will be longer. As for the maternal age, parity, systolic and diastolic blood pressure, infant weight, infant hight, infant sex, the results showed that there was no correlation between these and the duration of the third stage.

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Background: Blood culture is the criterion standard for identifying children with bacteremia. However, elevated false-positive rates are common and are associated with substantial health care costs. The aims of this prospective study were to: 1) determine the rate of blood culture contamination 2) determine variety and frequency of contaminant bacteria 3) compare the duration of hospital stay and antibiotic administration in patients with true bacteremia vs those have false positive blood culture.

Materials and Methods: Cross-sectional study conducted April through July 2004 among patients aged 14 years or younger who were admitted at Doctor Garib Children Medical Center of Tehran and had a blood culture obtained as part of their care. Bacterial isolates were identified to species level and medical records were reviewed in all cases with a positive blood culture. A number of clinical and laboratory criteria were used to deciding whether a blood isolate is a pathogen or a contaminant. These include the identify of the micro-organism itself, clinical features such as fever and leukocytosis the proportion of blood culture sets positive as a function of the number of sets obtained and to have an indwelling vascular catheter or prosthetic device.

Results: During the study period, 2877 sets of blood culture were evaluated and the rates of positive blood cultures associated with significant bacteremia and contamination were 1.04% and 5.4% respectively. Among the positive blood cultures, over the 84% of isolates were due to contamination and only 15.95% of isolated strains associated with true infection. The frequency of isolated bacteria with respect to true infection and contamination are as following: S. Aureus (infect: 9.0%, contam: 0.0%), S. Epidemidis (infec: 0.0%, contam: 13.3%), Micrococcus sp. (infec: 0.0%, contam: 4.3%), pseudomonas and related species other than P. aeruginosa (infec: 2.1%, contam: 60.6%), viridans group of streptococci (infec: 1.1%, contam: 2.1%), E.coli (infec: 1.06%, contam: 0.0%), Klebsiella pneumoniae (infec: 0.53%, contam: 0.0%), Enterobacter cloacae (infec: 0.53%, contam: 0.0%), and Acinetobacter baumannii (infec: 0.25%, contam: 0.53%). The mean of hospital stay for patients with true bacteremia, 14.83 days, was not significantly higher than that for patients with false-positive blood cultures (10.08 days). 43 patients had administrated one to three antibiotics after false-positive blood cultures.

Conclusion: The findings indicate that blood culture contamination rate in studied hospital is higher than standard levels, and very high rate of contamination with environmental pseudomonas species shows an unusuall epidemic condition. The findings also suggests high resource utilization and prolong patients stay due to pseudobacteremia.

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Background: One of the toxins accumulated in the body of hemodialysis patients is beta-2 microglobulin which is caused and increased by various factors. The one of this factors that can affect beta-2 macroglobulin is of membrane type that using in hemodialysis. In the present study, we examined the impact of C-reactive protein (CRP) as an inflammatory factor on beta-2 microglobulin in high-flux membrane hemodialysis patients. Methods: This cross-sectional study was done in 44 hemodialysis patients that have been dialyzed in two academic centers Sina and Amir Alam Hospitals, Tehran, Iran from 2013 to 2014. The patients were hemodialyzed via fistula or permanent catheters three times a week for 4 hours for more than three months. Patients with known infectious disease, hemodialysis with low-flux membrane and dialysis less than three times a week were excluded. All patients were hemodialyzed using Fresenius biocompatible high-flux membrane (FX 100, Fresenius, Massachusetts, USA). Arterial blood sampling was performed. beta-2 microglobulin, CRP, BUN and creatinine tests were conducted for all patients. Results: Forty-four patients among the chronic hemodialysis patients were selected for final analysis. 20 males (44.5%) and 24 females (54.5%) were included in this study. The frequencies of underlying disease in patients participating in the study were as follows: hypertension, 23 cases (52.3%) diabetes mellitus, 11 cases (25%) hypertension and diabetes mellitus, 2 cases (4.5%) obstructive disorder, 2 cases (4.5%). In 23 patients (52.3%), beta-2 macroglobulin was >12 mg/l and in 21 (47.7%), it was <12 mg/l. 29 cases (65.9%) had CRP values less than or equal 6 mg/l. However, there was no significant differences between beta-2 microglobulin and CRP levels (P= 0.460). Also regression analysis of data showed no relationship between beta-2 microglobulin and CRP levels (r= -047, P= 0.763). Conclusion: Although it seems that inflammatory factors can be effective in increasing beta-2 microglobulin, the present study did not find such a relationship between CRP and beta-2 microglobulin.