Israel Medical Association Journal

Background: Oral anticoagulation with warfarin can lead to life-threatening events as a result of either over-anticoagulation or undertreatment. One of the main contributors to an undesirable warfarin effect is the need to adjust its daily dose for a specific patient. The dose is adjusted empirically based on the experience of the clinician, a method that is often imprecise. There is currently no other well-accepted method for predicting the maintenance dose of warfarin.

Objective: To describe the application of an artificial neural network to the problem of warfarin maintenance dose prediction.

Methods: We designed a neural network that predicts the maintenance dose of warfarin. Data on 148 patients attending a large anticoagulant clinic were collected by file review. Using correlational analysis of the patients' data we selected the best input variables. The network was trained by using the back-propagation algorithm on a subset of our data and the results were validated against the rest of the data. We used a multivariate linear regression to create a comparable model.

Results: The neural network generated reasonable predictions of the maintenance dose (r = 0.823). The results of the linear regression model were similar (r = 0.800).

Conclusion: Neural networks can be applied successfully for warfarin maintenance dose prediction. The results are promising, but further investigation is needed.
 

Background: Cystoscopy, the principal means of diagnosis and surveillance of bladder tumors, is invasive and associated with unpleasant side effects

Objectives: To determine the early complications of rigid cystoscopy and the impact on patients' quality of life and sexual performance.

Methods: One hundred consecutive patients undergoing diagnostic rigid cystoscopy filled in questionnaires including anxiety and pain levels (0–5 visual analogue scale), adverse events, short-form health survey, International Prostate Symptom Score, and functional sexual performance. Questionnaires were administered before, immediately after, and 1, 2 days, 2 and 4 weeks following cystoscopy.

Results: The pre-cystoscopy anxiety level was 2.01. The average pain during the examination was 1.41. SF-36[1] score was not affected by cystoscopy. The subjective impact on patients' quality of life was 0.51. The mean IPSS[2] increased following cystoscopy (6.75 vs. 5.43, P = 0.001) and returned to baseline 2 weeks later. A decline in libido was reported by 55.6% (25/45) and 50% (3/6) of the sexually active men and women, respectively. Cystoscopy was associated with a decreased Erectile Dysfunction Intensity Score, from 15.6 to 9.26 during the first 2 weeks (P = 0.04). The overall complication rate was 15% and included urethrorrhagia and dysuria. None of the patients had fever or urinary retention and none was hospitalized. The complication rate was higher in patients with benign prostatic hyperplasia (24% vs. 9.7%, P = 0.001).

Conclusions: Rigid cystoscopy is well tolerated by most patients and has only a minor impact on quality of life. However, cystoscopy transiently impairs sexual performance and libido. The early complications are mild and correlate with a diagnosis of BPH[3].

Background: Erysipelas is a skin infection generally caused by group A streptococci. Although penicillin is the drug of choice, some physicians tend to treat erysipelas with antibiotics other than penicillin.

Objectives: To define the pattern of antibiotic use, factors affecting antibiotic selection, and outcome of patients treated with penicillin versus those treated with other antimicrobial agents.

Methods: A retrospective review of charts of adult patients with discharge diagnosis of erysipelas was conducted for the years 1993-1996.

Results: The study group comprised 365 patients (median age 67 years). In 76% of the cases infection involved the leg/s. Predisposing condition/s were present in 82% of cases. Microorganisms were isolated from blood cultures in only 6 of 176 cases (3%), and Streptococcus spp. was recovered in four of these six patients. Cultures from skin specimens were positive in 3 of 23 cases. Penicillin alone was given to 164 patients (45%). Other antibiotics were more commonly used in the second half of the study period (P < 0.0001) in patients with underlying conditions (P = 0.06) and in those hospitalized in the dermatology ward (P< 0.0001). Hospitalization was significantly shorter in the penicillin group (P= 0.004). There were no in-hospital deaths.

Conclusions: We found no advantage in using antibiotics other than penicillin for treating erysipelas. The low yield of skin and blood cultures and their marginal impact on manage­ment, as well as the excellent outcome suggest that this infection can probably be treated empirically on an outpatient basis.
 

Background: Cryosurgery is a minimally invasive treat­ment option for prostate cancer.

Objectives: To report on the first series of cryosurgical ablation for prostate cancer performed in Israel.

Methods: Cryosurgical ablation of the prostate was undertaken in 2 patients aged 53-72 diagnosed with adenocarcinoma of the prostate. The procedures were performed percutaneously and were monitored by real-time trans-rectal ultrasound. The CRYOHIT machine applying Argon gas was used with standard or ultra-thin cryoprobes. The average follow-up was 12.8 months postsurgery (range 1- 24 months).

Results: No rectal or urethral injuries occurred and all patients were discharged from hospital within 24-48 hours. The duration of suprapubic drainage was 14 days in 10 patients and prolonged in 2. Early complications included penoscrotal edema in four patients, perineal hematoma in three, hemorrhoids in two and epidydimitis in one. Long-term complications included extensive prostatic sloughing in one patient and a perineal fistula in another, both of whom required prolonged suprapubic drainage. Minimal stress incontinence was noted in two patients for the first 8 weeks after surgery. None of the patients has yet regained spontaneous potency. A prostate-specific antigen nadir of less than 0.5 ng/ml was achieved in eight patients and an undetectable PSA level below 0.1 ng/ml in five patients.

Conclusion: Cryoablation for prostate cancer is safe and feasible, and the preliminary results are encouraging. Further study is needed to elucidate the efficacy of the procedure.