Trimethoprim versus gentamicin for the prevention of bacteriuria following transrectal biopsy of the prostate--do patients need additional anaerobic cover?

OBJECTIVES: To study the incidence of aerobic and anaerobic bacteriuria in patients undergoing transrectal ultrasound-guided biopsies of the prostate. A comparative assessment of efficacy of trimethoprim with gentamicin for the prevention of bacteriuria following the transrectal biopsy of the prostate. To assess the need for additional prophylaxis against anaerobes for patients undergoing transrectal biopsies of the prostate gland. PATIENTS AND METHODS: In a pilot study during 1995-1997, all the patients undergoing transrectal ultrasound-guided biopsy of the prostate were randomised to receive either trimethoprim or gentamicin prophylaxis prior to the procedure. Midstream urine (MSU) samples were taken just prior to biopsy and 72 h later. A patient questionnaire to determine the symptoms of urinary tract infection (UTI) accompanied the 72-hour MSU request form. Urine samples were cultured aerobically, using a semiquantitative technique if dipstick analysis revealed the presence of blood, pus cell or nitrite. In addition to the routine aerobic culture, post-biopsy samples were also cultured for anaerobes by direct and enrichment methods. Bacteriuria was defined as a pure or mixed growth of 10(5) colony-forming units/ml. Fisher's test of exact probability was used for statistical analysis. RESULTS: 115 patients were available for final analysis. 53 had received gentamicin and 62 trimethoprim. Four patients had pre-existing bacteriuria (3.5%), 3 in the trimethoprim group and 1 in the gentamicin group. Post-operative bacteriuria developed in 5 patients given gentamicin (9.4%) and 1 given trimethoprim (1.6%). This difference was not statistically significant (p = 0.085). Post-procedure bacteriuria was asymptomatic in all but 1 case. Anaerobes were detected in only 5 MSUs (4.3%) post-biopsy. CONCLUSION: Though there was no statistical significant difference in the rates of bacteriuria following administration of trimethoprim and gentamicin, data appear to favour trimethoprim prophylaxis. Further studies are warranted. Transrectal biopsy of the prostate is associated with a low incidence of anaerobic UTI. In view of the very low incidence of anaerobic bacteriuria, routine antibacterial prophylaxis against anaerobes does not appear to be justified.

A combined medical and surgical approach to hydatid disease: 12 years' experience at the Hospital for Tropical Diseases, London.

BACKGROUND: There is no consensus as to the most appropriate treatment for the varied and often complicated presentations of hydatid disease in Britain. We looked at our own results over a 12-year period to see if a consistent and logical plan had emerged. PATIENTS AND METHODS: 70 patients presenting between 1986 and 1998 were analysed retrospectively, with regard to their presentation, diagnosis, treatment and outcome, with particular reference to the use of chemotherapy, and to the difficulties of post-treatment assessment by serology and imaging. RESULTS: 37 patients had been treated previously. 35 had hepatic cysts and 26 multiple cysts. 4 patients were treated by surgery alone, 44 by chemotherapy and surgery, and 14 by chemotherapy alone. The combined use of albendazole and praziquantel pre-operatively reduced significantly the number of cysts that contained viable protoscolices: 1/25 versus 5/8 that received albendazole alone (P = 0.00013). During the 12-year period, it became our policy to aim for 3 months drug treatment (albendazole throughout with praziquantel for 2 weeks), re-assess and proceed either to surgery or to continue with chemotherapy. CONCLUSIONS: It is possible to construct an algorithm for the management of patients with hydatid disease by chemotherapy and surgery, but the assessment of results by indirect techniques remains difficult.

31P NMR studies of human skin using a modified zig-zag surface coil.

Results are presented from an in vivo study of human skin in which a zig-zag surface coil together with a three-pulse Fourier Series Window (FSW) protocol have been used to obtain minimally contaminated 31P skin spectra of the posterior calf. Phantom experiments indicate that while the fall-off in the B1 field profile of the zig-zag surface coil is superior to conventional surface coil designs, it is still not sufficient on its own to reduce muscle signal contamination to acceptable levels in human studies. The additional spatial localization required is provided by the FSW, which reduces signal contamination to less than 30% of the total signal collected. In a study of 18 normal controls the measured pH was found to be relatively high (7.39 +/- 0.08), while the ratios of skin PCr/ beta-ATP (1.04 +/- 0.35) and PCr/Pi (1.67 +/- 0.4) were found to be low compared with that of skeletal muscle. In addition, substantial signal from phosphomonoesters and phosphodiesters were also observed.

Use of the Fourier series window protocol with a zig-zag surface coil in 31P NMR human skin spectroscopy. A theoretical study.

The use of a zig-zag surface coil with a three-pulse Fourier Series Window (FSW) has been suggested as a means by which in vivo NMR spectroscopic studies of human skin can be performed. Using direct numerical simulations of the magnetic field profile of a 10 limb zig-zag surface coil, the role of the FSW in reducing NMR signals originating from the deeper skeletal muscle layers is examined theoretically. The extent of muscle signal contamination is determined for different coil inter-limb spacings and pulse width settings. The optimum inter-limb spacing for studying living human skin, that which minimizes signal contamination and maximizes skin signal collected, is shown to be between 4 and 6 mm. These calculations demonstrate that the FSW and zig-zag surface coil offer a protocol for investigating the metabolism of large areas of surface tissue while keeping signal contamination from the deeper skeletal muscle layers down to an acceptable level.

Independent evaluation of impotence by colour Doppler imaging and cavernosometry.

Colour Doppler imaging and cavernosometry are the optimal means for objective assessment of pharmacologically induced penile erections. 21 impotent patients were assessed by both methods independent of the information derived from the other modality. The diagnosis obtained was found to be immediately consistent in only 10 cases, 7 of which had venous leakage. 6 of the remaining 11 patients had a diagnosis of mixed arterial and venous disease in one or the other modality, but only arterial or venous disease alone in the other. The remaining 5 patients had completely inconsistent diagnoses. However, knowledge of the clinical picture and awareness of the pitfalls in the diagnostic procedures allows most of the discrepancies to be explained. Colour Doppler imaging is subject to operator error but allows selection of patients for cavernosography.

Hyperparathyroidism after neck irradiation.

A retrospective review of 1550 cases of hyperparathyroidism (HPT) treated surgically over a 30-year period reveals a past history of exposure to neck irradiation in 10 cases (0.7 per cent). The indication for radiotherapy was benign disease in nine and papillary thyroid carcinoma in one case. The mean interval between radiation exposure and the detection of HPT was 32 years (range 3-63 years). Patients treated with radioactive iodine alone developed HPT after a mean of 5 years while the interval for those treated with external beam therapy alone was a mean of 44 years. The parathyroid histology was adenoma in six cases, carcinoma in three cases and nodular hyperplasia in one case. All patients had coincident benign thyroid disease apart from one that had previously had papillary carcinoma and another with follicular carcinoma. Neck irradiation has been shown to confer an increased risk of HPT due to parathyroid adenoma and carcinoma. Radiotherapy for benign disease has generally been abandoned and these cases demonstrate a further contra-indication for the use of neck irradiation.

Mast cells and IgE-mediated release of histamine and arachidonate metabolites from human kidney.

We report a pilot study of mast cells and IgE-mediated release of histamine, leukotrienes and thromboxanes from human kidney. The results together with previous findings in the guinea-pig and rat suggest that mast cells and IgE may play an important role in kidney disease.

Kidney mast cells, IgE and release of inflammatory mediators capable of altering renal haemodynamics.

Collagenase-dispersed human, guinea pig and rat kidney cells, actively or passively sensitized with IgE or IgG subclasses, released histamine, leukotriene C4 and thromboxane B2 on challenge with the specific antigen or antisera to mast-cell-sensitizing immunoglobulins. A similar reaction occurred in the isolated perfused kidney of sensitized guinea pigs, which additionally showed vasoconstriction. Mast cells were identified in cell suspensions and tissue sections. These findings provide support for the possible role of IgE and mast cells in renal pathophysiology.

The radiological appearances of the liver after surgical removal of hydatid cyst.

Simple excision of a hydatid cyst from the liver leaves a residual cavity. Depending upon the surgical management of the cavity this can appear cystic, hypoechoic or echogenic on subsequent ultrasound examination. Negative attenuation values on computed tomography are typical of omentoplasty. These appearances can mimic pathological lesions in the liver. Knowledge of the site and nature of previous surgery can prevent diagnostic confusion.

Morbidity in adult parathyroid surgery.

The results of surgery in a series of 700 consecutive cases of primary and tertiary hyperparathyroidism are reported with especial reference to mortality and morbidity. Providing that the operation is a first or second operation and that the patient is below 70 years of age, the operation has been found to be safe and uncomplicated.

Experience with mebendazole in the treatment of inoperable hydatid disease in England.

Eleven heterogeneous patients with inoperable hydatid disease were treated with high doses of oral mebendazole, up to 200 mg/kg/day for 16 to 48 weeks. Toxicity was not encountered. Despite careful assessment it proved difficult critically to evaluate the efficacy of mebendazole. In four patients chemotherapy appeared to have been at least partially successful and success seems to have correlated with serum levels in excess of 100 ng/ml one to three hours after dosage. The problems of assessment are discussed and the need for controlled trials of mebendazole in hydatid disease are stressed.

Ectopic parathyroid adenomas.

Two cases of parathyroid tumours occurring in unusual situations are described. Such cases may cause difficulty in both the diagnosis and the surgical treatment of hyperparathyroidism. The cases described illustrate the importance of a definitive aetiological diagnosis in hypercalcaemia, if appropriate surgery is to be performed. The value of discriminant function analysis and hydrocortisone suppression tests are discussed.

Ureteric involvement with abdominal aortic aneurysm.

The clinical presentations of 3 patients found to have an abdominal aortic aneurysm with ureteric involvement have been described. The world literature concerning this problem and methods of surgical treatment have been reviewed. The importance of medial displacement of the ureters as an early diagnostic sign indicating the presence of an abdominal aortic aneurysm is again emphasised. The possibility of a relatively benign course for the aneurysm should be considered in patients with renal or cardiorespiratory complications. In such cases, treatment of the ureteric involvement alone is justified.