Risk factors of recurrent anal sphincter ruptures: a population-based cohort study.

OBJECTIVE: To determine the incidence and risk factors of recurrent anal sphincter rupture (ASR). DESIGN: Population-based retrospective cohort study. SETTING: Data were taken from the National Medical Birth Registry, Denmark. POPULATION: Patients with a first and a second vaginal delivery in the time period 1997-2010. METHODS: Univariate analysis and multivariate logistic regression were used to determine risk factors of recurrent ASR. MAIN OUTCOME MEASURES: The incidence of recurrent ASR and odds ratios for possible risk factors of recurrent ASR: age, body mass index, grade of ASR, birthweight, head circumference, gestational age, presentation, induction of labour, oxytocin augmentation, epidural, episiotomy, vacuum extraction, forceps, shoulder dystocia, delivery interval and year of second delivery. RESULTS: Out of 159 446 women, 7336 (4.6%) experienced an ASR at first delivery, and 521 (7.1%) had a recurrent ASR (OR 5.91). The risk factors of recurrent ASR in the multivariate analysis were: birthweight (adjusted OR, aOR, 2.94 per increasing kg, 95% CI 2.31-3.75); vacuum extraction (aOR 2.96, 95% CI 2.03-4.31); shoulder dystocia (aOR 1.98, 95% CI 1.11-3.54); delivery interval (aOR 1.08 by year, 95% CI 1.02-1.15); year of second delivery (aOR 1.06, 95% CI 1.03-1.09); and prior fourth-degree ASR (aOR 1.72, 95% CI 1.28-2.29). Head circumference was a protective factor (aOR 0.91 per increasing cm, 95% CI 0.85-0.98). CONCLUSIONS: The incidence of recurrent ASR was 7.1%. Risk factors of recurrent ASR were excessive birthweight, vacuum extraction, shoulder dystocia, delivery interval, year of second delivery and prior fourth-degree ASR. A larger head circumference reduced the risk of recurrent ASR.

Defects on endoanal ultrasound and anal incontinence after primary repair of fourth-degree anal sphincter rupture: a study of the anal sphincter complex and puborectal muscle.

OBJECTIVES: To perform three-dimensional endoanal ultrasound (EAUS) after primary repair of fourth-degree anal sphincter rupture (ASR) and correlate the sonographic defects with anal incontinence (AI); to measure the axial and sagittal thickness and angle of the puborectal muscle (PRM) as well as the length of the anal canal, and then correlate these measures with AI; and to assess the interobserver measurement agreement between an inexperienced and an experienced sonologist. METHODS: EAUS was offered to 84 consecutive women, who were asked to answer a validated questionnaire after fourth-degree ASR. AI was graded according to the Wexner score and EAUS defects were graded according to the Starck score. RESULTS: Sixty-one women (73%) answered the questionnaire. The median (range) follow-up time was 5.1 (1.3-8.7) years. Thirty-three (54%) of these women underwent EAUS and were included in the study. There was no difference in the incontinence scores between women who underwent EAUS and those who did not. Eleven of the women who underwent EAUS (33%) were continent, 22 women (67%) had flatus incontinence at least once a month, of whom 12 also had incontinence for liquid stool and two had incontinence for solid stool. The median Wexner score was 2 (range, 0-12). Five of the patients (15%) had no ultrasound defects. All of the patients with Wexner scores > or = 4 had a Starck score of > or = 10. No association between ultrasound defects and AI was demonstrated, however, the angle of the PRM and parity were associated with Starck score. No clear association between the measurements of the PRM and AI was shown. The experienced observer detected more of the small defects than did the inexperienced observer. CONCLUSION: In a 1-9-year follow-up period after primary suture of fourth-degree ASR, the frequency of AI was high, at 67%. No clear association was seen between AI and sphincter defects detected on ultrasonography. There was an association between the angle of the PRM and the extent of ultrasound defects.

[Cyanide-resistant oxygen consumption of the lysine-synthesizing bacteria Brevibacterium flavum 22 LD]. / Tsianidrezistentnoe potreblenie kisloroda u lizinsinteziruiushchikh bakterii Brevibacterium flavum 22LD.

The growth of the culture and biosynthesis of lysin were studied in Brevibacterium flavum 22 LD cultivated in a chemostat. During cultivation the flow rate of the medium and the partial pressure of oxygen dissolved in the medium were varied. The maximum yield of lysine, calculated in respect to the sucrose consumed, (Yp = g lysine . HCl/g sucrose) was registered when cyanide-resistant oxygen consumption was the least. A change of the cultivation conditions provoked a decrease of Yp value and a simultaneous increase in cyanide-resistant respiration. Possible reasons of the phenomena observed are discussed.