Infection of hemodialysis catheters: incidence and mechanisms

Fifty-three consecutive subclavian or jugular hemodialysis catheters inserted into 41 patients were prospectively studied over a period of 8 months in order to determine the incidence of infection and its mechanisms. The intravascular, intradermal and the Y catheter segments as well as both connections were cultured using a quantitative technique for the intraluminal surface. In addition, the intravascular and intradermal portions of the catheter were cultured using a semiquantitative technique for the external surface. Skin smears of the catheter entry site were also cultured, and blood cultures were similarly obtained if fewer developed. Twenty-nine of the 53 catheters (55%) were significantly colonized by one (19 cases) or more (10 cases) microorganisms. The source of the colonizing microorganisms was the skin in 17 cases (58%), intraluminal in 5 (17%), both routes in 5 (17%) and others in 2 (6.8%). Staphylococcus epidermidis (22 cases) and Staphylococcus aureus (4 cases) were the bacteria most frequently isolated. Nine of the 53 catheterizations (17%) were complicated by catheter-related septicemia due to S. aureus in 4 cases, S. epidermidis in 3 cases, Streptococcus faecalis in 1 and Proteus vulgaris in 1. Catheter-related bacteremia contributed to a patient's death in 1 case. Suppurative local infections of the catheter entry site developed in 3 cases, 2 of them with septicemia. We conclude that the rate of infection due to subclavian or jugular hemodialysis catheters is very high and that the skin is the most frequent origin of the microorganisms.     

Granulocyte growth factors: Achieving a consensus

A consensus meeting held under the auspices of the EuropeanSchool of Oncology concluded that the use of granulocyte growthfactors is definitely indicated, or acceptable given existingevidence, in the following circumstances: to alleviate congenitalneutropenia; in the mobilisation of peripheral blood progenitorcells for autotransfusion; to encourage engraftment followingbone marrow transplantation and in cases of failed engraftment;to support continuationof ganciclovir anti-CMV therapy in certainpatients with AIDS, where the switch to foscarnet is contraindicatedor where toxicity to foscarnetdevelops. It was also agreed that there is an overwhelming need for carefullycontrolled clinical trials in a wide range of indications inwhich growth factor use may improve outcome. In the majorityof tumours, the possible benefit of dose optimisation and intensification,and therefore the role of growth factors in support of suchmeasures has still to be defined. Extramedullary toxicitiesmay in these instances become dose limiting. growth factors, neturopenia, peripheral blood, progenitor cells, bone marrow transplantation, AIDS     

Vertebral arch tuberculosis in two human immunodeficiency virus-seropositive heroin addicts

We studied two cases of disseminated tuberculosis with vertebral arch involvement in drug addicts seropositive for human immunodeficiency virus. The first patient developed a paraplegia while he was recovering from a meningeal tuberculosis. On the abdominal plain roentgenogram, the right transverse process of L-2 was absent, and a computed tomographic scan revealed destruction of the right vertebral arch together with a collection in the paravertebral area. The second patient had miliary tuberculosis and complained of lumbar pain. The radiologic findings were similar to those in the first case, but at the L-4 level.     

Spontaneously recurrent seizures after intracerebral injections of kainic acid in rat: a possible model of human temporal lobe epilepsy

Intrastriatal injections of kainic acid in rats acutely induced repeated episodes of clonic convulsions. Spontaneously recurrent generalized seizures and a potentiation of the convulsant effects of pentylenetetrazol were then observed in most of the injected rats several weeks after surgery. In addition to marked loss of striatal neurons, limbic pathological alterations similar to those found in human temporal lobe epilepsy were observed in the brains of the kainic-acid treated rats. It is proposed that this preparation might serve as an animal model of human temporal lobe epilepsy.     

A prospective Phase II trial of using extracranial stereotactic radiotherapy in primary and metastatic renal cell carcinoma

A retrospective study has indicated that stereotactic radiotherapy (SRT) has a value in treating both primary tumors and singular metastatic lesions that cause local symptoms. Here we present the results of a prospective study evaluating the safety and local efficacy of SRT in metastatic or inoperable primary renal cancer. Thirty patients with metastatic renal cell carcinoma (RCC) or inoperable primary RCC received high-dose fraction SRT. In total, 82 lesions were treated. Dose/fractionation schedules varied depending on target location and size. The most frequently used fractionations were 8 Gy×4, 10 Gy×4, 15 Gy×2 or 15 Gy×3 prescribed to the periphery of the PTV. Local control, defined as radiologically stable disease (SD) or partial/complete response (PR/CR) was obtained in 98% of treated lesions but 19% of lesions were in patients with a follow time of less than 6 months. CR was observed in 21% of the patients and 58% of the patients had a partial volume reduction or local stable disease after a median follow-up of 52 months (range 11-66) for patients alive and 18 months (range 4-57) for deceased patients. Local progression was seen in two lesions. Side effects were grade I-II in 90% of cases. The overall survival was 32 months. SRT for patients with primary and metastatic RCC resulted in high local control rate with generally low toxicity. The method can thus be considered a therapeutic option to surgery in patients with a limited number of metastases, as local treatment in RCC with an indolent presentation or as a method of reducing tumor burden prior to medical treatment.     

Decreased pregnancy rate after in-vitro fertilization in HIV-infected women receiving HAART

A study on in-vitro fertilization (IVF) was conducted among HIV-infected women. In these patients, a reduced pregnancy rate after IVF was observed if the patient's own oocytes were used. However, no significant reduction in the pregnancy rate was found if donated oocytes were used. The CD4 lymphocyte count was independently associated with ovarian resistance to hyperstimulation. Subclinical hypogonadism mediated by immunosuppression may explain these observations, suggesting the need to optimize the immunological status of the patient before considering assisted reproduction treatments.     

Systematic review of clinical trials evaluating low doses of stavudine as part of antiretroviral treatment

Stavudine is a nucleoside analogue used for the treatment of HIV-1 infection, as part of highly active antiretroviral treatment. In developing countries, stavudine is used widely, owing to low cost and inclusion in generic fixed-dose combinations. In developed countries, stavudine is now rarely used, although it is highly effective. This is because newer drugs show lower rates of mitochondrial toxicities, such as lipoatrophy, peripheral neuropathy and lactic acidosis. In the development of stavudine, there was evidence that a dosage of 20-30 mg b.i.d. was effective, but the 40-mg b.i.d. dose gained regulatory approval. This review analyses the clinical trials conducted before and after the regulatory approval of stavudine, and shows that the dose of 30 mg b.i.d. has equivalent antiviral efficacy (given the caveats of meta-analysis), with some evidence of lower rates of peripheral neuropathy and lipoatrophy. With limited resources for HIV-1 treatment in developing countries, and only 25% of eligible patients receiving highly active antiretroviral treatment, low-cost treatment options such as stavudine still need to be pursued, if safety can be improved by dose optimisation.