Primäres Lymphom des zentralen Nervensystems als Neuromanifestation im AIDS-Stadium

In patients infected with human immunodeficiency virus (HIV), the risk of developing non-Hodgkin's lymphoma is over 100 times greater than with noninfected persons. Primary central nervous system lymphoma as a complication of the acquired immunodeficiency syndrome (AIDS) occurs in up to 2.4% of all cases and is strongly associated with the Epstein-Barr virus. The prognosis is very poor, with a mean survival time of 21 to 27 days without therapy and up to 119 days with radiation therapy. We describe the course of seven AIDS patients with histologically proven primary central nervous system lymphoma and present a review of clinical symptoms, diagnosis, and therapy. The main criteria for differential diagnosis from other secondary neuromanifestations such as cerebral toxoplasmosis, progressive multifocal leukoencephalopathy, abscesses, and infarctions are described.     

CAS-System MKM(R): use and results in lateral skull base surgery

BACKGROUND: Computer assisted surgery has reached an advanced stage of development and offers new possibilities in daily surgical procedures. METHODS: The MKM(R) - is a navigation system fitted with a laser-guided, autofocus-microscope for referencing purposes. The coordinates can be set using various marker systems and a special workstation is used for preoperative planning. It is possible to add landmarks and display them in the surgeon's eyepiece. The clinical integration, the time required for the use of the navigation system and the intraoperative accuracy of the system were evaluated on the basis of 136 lateral skull base procedures. RESULTS: The degree of accuracy is determined by the type, amount and positioning of markers. The adjustment of reference points should be carried out following macrosurgery in order to avoid shifting factors. For an additional increase in accuracy, an improvement in the spatial resolution of the CT scans is required, with a section thickness of 1 mm and a pixel size of 0.5mm. The bone-anchored structures of the temporal bone do not underlie shifting or extensive intraoperative swelling. Skull base surgery is, therefore, ideally suited for the application of CAS. We found that registration was accurate to less than 1 mm (0.68 mm +/- 0.17 mm) and that the MKM(R) system made an additional contribution to surgical safety by identifying important structures. CONCLUSIONS: A practical accuracy found to be approximately one millimetre suggests that the non-invasive referencing system may be effective, accurate and useful for computer assisted identification of vital structures. We expect navigation systems to improve the quality and reduce the risks of surgical intraventions.     

The nutritional response to home enteral nutrition in childhood

The nutritional response to home enteral nutrition (HEN) was evaluated in a prospective study of 44 consecutive children (median age 48 months) who received HEN for more than 1 month (median duration 6 months). Three groups were studied: 17 children were stunted, 14 were wasted and 13 were adequately nourished but unlikely to maintain oral intake during anticipated nutritional stress. In the stunted group (median duration of HEN 15 months) there was a significant correlation between improvements in height–for–age z scores and duration of feeds ( r = 0.63; p = 0.006). In the wasted group (median duration of HEN 4 months) all anthropometric indices improved significantly ( p < 0.05). HEN was also successful in maintaining nutritional status in the third group. Thus, supplementary HEN is an effective method of nutritional support for a variety of indications, provided concurrent advice from a nutritional care team is available.     

Event-related potentials in HIV-infected outpatients.

Event-related potentials (ERP) were determined in 138 human immunodeficiency virus (HIV)-infected outpatients and 92 healthy controls of a corresponding age. Of the HIV-infected patients, 31.8% showed an abnormal latency of the P3-component of ERPs (P3-ERP), exceeding the mean value + 2 SD of P3-ERP latencies from age-matched healthy subjects. From the untreated patients in stage Walter Reed (WR) = 6, 71.4% had abnormal P3-ERP latencies, whereas in WR = 2, only 19.6% of P3-ERPs were abnormal. Fourteen patients were observed over a period of 3-16 months. P3-ERP latencies were shortened in 7 patients under treatment with zidovudine. A marked increase in P3-ERP latencies was observed in 7 untreated HIV-infected patients. It is assumed that ERPs are a useful neurophysiological method to detect early cerebral dysfunction in HIV-infected patients.     

Diagnosis and clinical associations of zinc depletion following bone marrow transplantation

Following the emergence of biochemical zinc deficiency after bone marrow transplantation, the clinical value of plasma alkaline phosphatase activity as an early indicator of biochemical zinc depletion was investigated in this group of patients. Serial measurements of plasma zinc and alkaline phosphatase activities in 28 consecutive children (median age 8.7 years; 16 males) undergoing bone marrow transplantation were carried out and clinical associations recorded. A significant fall in plasma zinc occurred after the bone marrow transplant, and 19 children developed biochemical zinc deficiency (Zn < 11 mumol/l) at a median of 7 days following the transplant. Zinc depletion was more common in younger patients and in children with diarrhoea. A positive correlation was found between plasma zinc and alkaline phosphatase activities. Zinc depleted patients had more febrile episodes of longer duration and were more likely to have a positive blood culture. Haemopoetic recovery was not affected by zinc deficiency. Following zinc supplementation, alkaline phosphatase showed a significant increase. The sensitivity of a low alkaline phosphatase as a screening test for biochemical zinc deficiency was 83%, with a specificity of 86%. Low alkaline phosphatase activity following bone marrow transplant is an indication for zinc supplements.     

OCCUPATIONAL ASTHMA IN A CHEESE PACKER

Occupational asthma is an increasingly common clinical problem.¹ A worker who develops asthma for the first time when starting work in a new environment may be straightforward to diagnose. However, when asthma occurs after a latent period following initial exposure, or when a pre-existing asthmatic develops work-related symptoms, the occupational link may be less easy to appreciate. This case report concerns a cheese factory worker with pre-existing asthma who experienced severe symptoms when a new process was introduced for drying grated cheese and was able to return to work only after the process was modified. The drying agent responsible has not been previously reported as a cause of asthma.     

High-signal lesions in the midbrain on T1-weighted MRI in an HIV-infected patient

In addition to opportunistic infections, neoplasms or cerebrovascular complications, metabolic encephalopathies are a classical cause of diffuse brain dysfunction in HIV infection and are frequent in the terminal stage. We report an HIV-infected patient with symmetrical, focally increased signal in the midbrain on proton density- and T1-weighted MRI without corresponding high signal on T2-weighted images or on CT. While the precise nature and cause of this uncommon finding is not fully understood, the available evidence suggests that these lesions might represent a novel metabolic encephalopathy. Received: 15 December 1995 Accepted: 26 March 1996     

FIRST-LINE TREATMENT IN ACUTE NON-DYSENTERIC DIARRHOEA: CLINICAL COMPARISON OF LOPERAMIDE OXIDE,LOPERAMIDE AND PLACEBO

SUMMARY The use of antimicrobial agents for the treatment of acute diarrhoea has become more common with the introduction of quinolone compounds, which are active against most types of bacterial pathogens. Despite the fact that such drugs have been used for empirical therapy or even for prophylaxis, current opinion would restrict their use to specific groups of patients who are likely to show particular benefit from them. Non-specific therapy seems a more appropriate initial treatment for cases of acute, non-dysenteric diarrhoea. Clinical trial data are presented here comparing the effects of loperamide oxide 1 and 2 mg to those of placebo and loperamide 2 mg in this condition. All the drug preparations were significantly superior to placebo, in particular reducing the time to complete relief of symptoms to about 24 hours, as opposed to 45 hours on placebo treatment. Of these preparations, loperamide oxide 1 mg is to be preferred, as it produces fewer constipation-like episodes after treatment. The introduction of loperamide oxide 1 mg represents a useful advance in the non-specific treatment of acute, non-dysenteric diarrhoea.     

On the mechanism of the effects of potassium restriction on blood pressure and renal sodium retention

Dietary potassium restriction increases sodium and chloride retention, whereas potassium administration promotes both diuresis and natriuresis. In epidemiologic and clinical studies, potassium intake is inversely related to blood pressure and is lower in blacks than in whites. The present studies examined the mechanism by which potassium restriction fosters sodium conservation and the impact of race on this response. Twenty-one healthy black and white men and women ingested an isocaloric, potassium-restricted diet (20 mmol/d) containing 180 mmol/d of sodium with and without a potassium supplement (80 mmol/d) for 9 days on two occasions. Additionally, eight of these subjects ingested the same diets for 3 days followed by a water load to determine free water clearance before and during the early phase of dietary potassium restriction. During potassium restriction, mean arterial pressure (MAP) derived from 24-hour blood pressure measurements was higher (85.7 +/- 1.6 mm Hg v 82.0 +/- 1.3 mm Hg; P < 0.001), cumulative sodium excretion lower (984 +/- 59 mmol/d v 1,256 +/- 58 mmol/d; P < 0.001), and weight greater (71.1 +/- 2.1 kg v 69.3 +/- 2.2 kg; P < 0.001). Blacks displayed no greater increase in MAP, although they excreted less sodium overall and less potassium on the potassium-supplemented diet. After a water load, minimum urine osmolality (Uosm) was lower (53.0 +/- 3.0 mOsm/L v 65.6 +/- 3.5 mOsm/L; P = 0.01) and free water clearance greater (4.44 +/- 0.59 mL/min v3.72 +/- 0.58 mL/min; P = 0.009) during potassium restriction. In conclusion, in healthy, normotensive subjects, potassium restriction was associated with an increase in blood pressure and volume expansion effected by increased renal sodium and chloride retention. Potassium restriction was also associated with increased free water clearance and enhanced diluting capacity consistent with augmentation of Na+, K+:2Cl- cotransporter activity in the thick ascending limb of Henle. This mechanism may play an important role in the renal adaptation required for potassium conservation, but at the expense of sodium chloride retention and an elevation in blood pressure.