The management of musculoskeletal infection in HIV carriers

Over a three-year period, the authors prospectively implemented a protocol for management of musculoskeletal sepsis (MSS) in HIV carriers in Yaounde, Cameroon. The diagnosis of MSS was based on conventional criteria. HIV carriage was screened by an ELISA test and confirmed with the Western Blot technique. The immune status was based on CD4 lymphocyte count by flow cytometry; patients were classified as non-immunodepressed (NID), mildly immunodepressed (MID), or severely immunodepressed (SID) based on their CD4 lymphocyte count, as the latter was respectively over 500, between 200 and 500 or less than 200 per ml. Infection was treated by surgical debridement followed by a long-course targeted antibiotic therapy. All SID patients and some MID patients with AIDS-related symptoms also had standard antiretroviral (ARV) therapy. Thirty-one of 294 patients seen with musculoskeletal sepsis during the study period and tested for HIV were found to be HIV carriers. Their mean age was 33 years; the male/female ratio was 1.58. The following clinical pictures were observed: chronic osteomyelitis (COM) in 32.3% of the cases, septic arthritis (SA) in 38.7%, soft tissue infection (STI) in 25.8%; the last case was a severe leg complication of Buruli Ulcer (BU). Among these 31 patients, 38.7% were classified as SID (5 COM, 4 SA, 2 STI and the BU patient), 25.8% as MID (2 COM, 4 SA, 2 STI) and 35.5% as NID (3 COM, 6 SA, 2 STI). The organisms involved were not specific. Fifteen patients were managed conventionally, while the other 16 had the usual treatment associated with ARV therapy. The immediate outcome of MSS was good in 29 patients, after a mean hospital stay of five weeks; in two cases of septic arthritis of the knee, a second debridement was needed, due to persistent drainage, and the sinuses all closed. Three months after discharge, one patient with COM of the humerus developed a low-flow fistula which was closed after a revision sequestrectomy. After one year, none of the patients complained of any symptom suggesting reactivation of their MSS. There is no evidence that HIV carriage is in itself a high risk factor for musculoskeletal sepsis; the incidence of HIV carriage was indeed virtually similar in the 294 patients with MSS and in the general population, i.e. around 10%. However, in order to improve the outcome following musculoskeletal infections in patients with HIV, their management should take into account their immune status, based on a CD4 lymphocyte count. NID patients should be treated as any other patients with MSS, while SID should have additional standard ARV treatment. For those who are MID, the indication for antiretroviral therapy should depend on the presence of one or more AIDS-related signs.     

Randomized prospective study comparing high-dose-rate intraluminal brachytherapy (HDRILBT) alone with HDRILBT and external beam radiotherapy in the palliation of advanced esophageal cancer

PURPOSE: HDRILBT is one of the best methods of palliation for advanced esophageal cancer (AEC) by improving dysphagia-free survival (DFS) and overall survival (OS). This study examines if the addition of EBRT would further improve the outcome by improving DFS in AEC. METHODS AND MATERIALS: Patients with inoperable AEC were entered into a randomized prospective study. HDRILBT of 16 Gy/2 fractions/3 days was given initially to all patients. Following treatment, patients were randomized to receive no further treatment (Group A) or additional EBRT of 30 Gy/10 fractions/2 weeks (Group B) and were followed for 1 year. Statistical analysis of the data was done using the SAS statistical software package (SAS Institute, Cary, NC). Prognostic variables were analyzed using the chi(2) and log-rank tests and survival curves were drawn using the Kaplan-Meier method. Multivariate survival analysis was done using the Cox proportional hazards model. RESULTS: Sixty patients were entered into the study. Patient and tumor characteristics were comparable among the groups. Of 30 patients in Group B, 2 refused additional EBRT (no dysphagia). At 6 months, >50% had DFS in both groups and this was comparable. There was no difference statistically (p >0.05) in the DFS and OS between the two groups at the end of 12 months. Median survival for Group A was 7.23 months and 7.5 months for Group B. Additional EBRT did not improve DFS or OS. Eleven patients developed strictures related to radiotherapy and were dilated successfully (Group A, 7; Group B, 4; p >0.05). Four patients had progressive luminal disease which progressed to fistula (Group A, 3; Group B, 1; p >0.05). There was no effect of any patient or treatment parameter on DFS. Presenting weight and ECOG score had an impact on OS. CONCLUSIONS: From the preliminary analysis, additional EBRT to HDRILBT does not improve DFS or outcomes in inoperable AEC.     

External jugular vein vascular malformation: sonographic and MR imaging appearances

Vascular malformations arising from the wall of the external jugular vein are rare. This case series discusses the sonographic and MR imaging appearances of four such cases and reviews the literature. The diagnosis should be suggested preoperatively particularly because of the close relationship such malformations to the external jugular vein, as this helps surgeons to plan the operative procedure. The imaging appearances are similar to those of other vascular malformations elsewhere in the head and neck.     

Characterization of an aquaporin-2 water channel gene mutation causing partial nephrogenic diabetes insipidus in a Mexican family: evidence of increased frequency of the mutation in the town of origin

A Mexican family with partial congenital nephrogenic diabetes insipidus (NDI) that resulted from a mutation in the aquaporin-2 water channel (AQP2) was characterized, and the source of this rare mutation was traced to the family's town of origin in Mexico. Affected individuals with profound polyuria and polydipsia were homozygous for an autosomal recessive missense V168M mutation in the AQP2 gene. Expression in oocytes revealed that, although retained in the endoplasmic reticulum (ER) to a great extent, a considerable amount of the partially functional AQP2-V168M was expressed at the plasma membrane, and that its ER retention was less than AQP2-T126M, a functional mutant in severe recessive NDI. None of the affected AQP2-V168M individuals had neurologic deficits, which also suggested a milder form of the disease. The homozygous individuals reported subjective improvement in polyuria and polydipsia with the use of dDAVP (1-desamino-8-D-arginine-vasopressin). When clinically tested, infusion of dDAVP at variable doses produced a partial increase in the urinary osmolality in homozygous individuals and decreased their water intake. Heterozygotes were unaffected when compared with controls. Samples were obtained from the population of the Mexican town of origin of the family; 30% of the population was heterozygous for the V168M AQP2 mutation and 1% was homozygous for the mutation. The high frequency of this rare mutation in the town provides evidence for an important health care problem in the village with consequences for future generations.     

Regional anesthesia techniques for the lower extremity

This article focuses on regional anesthesia for orthopedic procedures of the lower extremity.     

Differential oblique angle spectroscopy of the oral epithelium

Increasing evidence suggests that inflammation may contribute to the process of carcinogenesis. This is the basis of several clinical trials evaluating potential chemopreventive drugs. These trials require quantitative assessments of inflammation, which, for the oral epithelium, are traditionally provided by histopathological evaluation. To reduce patient discomfort and morbidity of tissue biopsy procedures, we develop a noninvasive alternative using diffuse reflectance spectroscopy to measure epithelial thickness as an index of tissue inflammation. Although any optical system has the potential for probing near-surface structures, traditional methods of accounting for scattering of photons are generally invalid for typical epithelial thicknesses. We develop a single-scattering theory that is valid for typical epithelial thicknesses. The theory accurately predicts a distinctive feature that can be used to quantify epithelial thickness given intensity measurements with sources at two different angles relative to the tissue surface. This differential measure approach has acute sensitivity to small, layer-related changes in scattering coefficients. To assess the capability of our method to quantify epithelial thickness, detailed Monte Carlo simulations and measurements on phantom models of a two-layered structure are performed. The results show that the intensity ratio maximum feature can be used to quantify epithelial thickness with an error less than 30% despite fourfold changes in scattering coefficients and 10-fold changes in absorption coefficients. An initial study using a simple two-source, four-detector probe on patients shows that the technique has promise. We believe that this new method will perform well on patients with diverse tissue optical characteristics and therefore be of practical clinical value for quantifying epithelial thickness in vivo.     

Physiological and behavioural responses to duodenal pain in freely moving rats

Luminal distention of the intestine can be aversive in humans and laboratory animals, and hypersensitivity to distention is found in functional gastrointestinal disorders. Current animal models either require anaesthesia or acute balloon intubation or use implanted balloons of irritant materials, for which the aversive quality of distention and physiological responses have not been well characterised. We report here that silicone balloon catheters implanted in the duodenum via the stomach have long patency without obvious tissue damage. Balloon inflation in freely moving rats caused passive avoidance learning and classic 'pain' postures, as well as graded cardiovascular responses which can be recorded telemetrically. The method should make long-lasting studies of pharmacological and environmental effects on visceral sensitivity more feasible.