Biomedical subjects

J K Rockstroh

Publications and source records attributed to J K Rockstroh.

99 records · Page 6Linked to original sources

PubMed1991

[A case of AIDS-associated histoplasmosis in Germany].

In a thirty-year-old patient with AIDS the diagnosis of disseminated histoplasmosis was established via biopsy and culture. The patient had grown up in Argentina, where histoplasmosis is endemic. He had not been in an endemic region during the last two years anteceding the manifestation of systemic histoplasmosis. Accordingly, in patients with a progressive immunodeficiency syndrome, reactivation of a former (possibly inapparent) infection with Histoplasma capsulatum must be considered. Therapy with Amphotericin B lead to a remarkable improvement of clinical, laboratory and sonographic findings. Due to the fact that total eradication of H. capsulatum from the infected host cannot be achieved with any known drug regimen, a life-long follow-up therapy was begun. The patient showed no signs of relapse after a follow-up of 7 months.

Acquired Immunodeficiency Syndrome↗

PubMed1991

Antihypertensive therapy. To stop or not to stop?

The benefits of continuous antihypertensive therapy have been extensively documented. However, lack of compliance with the prescribed regimen, excessive cost, and troublesome adverse effects of some antihypertensive agents led to the consideration of intermittent therapy or even complete discontinuation of therapy as an effective alternative to lifelong medication. Prospective studies dealing with this subject reported inconsistent results. Nevertheless, they allowed us to identify selection criteria of candidates for step-down or discontinuation of antihypertensive therapy. Such candidates include patients with mild essential hypertension who have one or more of the following characteristics: young age, normal body weight, low salt intake, no alcohol consumption, low pretreatment blood pressure, successful therapy with one drug only, and no or only minimal signs of target organ damage. Stopping antihypertensive therapy without subsequent rise in arterial pressure was shown to be possible in a subset of patients with mild essential hypertension for a period of months to years. This approach appears to be safe, provided that blood pressure is monitored frequently, and may improve compliance, save treatment costs, and reduce adverse effects of certain drugs, although its long-term consequences for morbidity and mortality remain to be determined.

Antihypertensive Agents↗

PubMed1991

Elevated serum activity of N-acetyl-beta-glucosaminidase in essential hypertension: diagnostic value and reversal to normal values after antihypertensive therapy.

Previous studies have shown that urinary N-acetyl-beta-glucosaminidase (NAG) is elevated in patients with hypertension, even without renal disease. To elucidate the value of measuring NAG, both in urine and serum of hypertensive patients, we measured NAG activity in the serum, plasma, and 24-hour urine by the fluorimetric method in 84 patients with uncomplicated essential hypertension before and after 6 months of effective treatment. NAG activities of these hypertensive patients were compared with those of 102 healthy normotensive subjects and 97 patients with various renal diseases and controlled hypertension. Serum NAG activity was clearly greater in patients with essential hypertension (427 +/- 124 U/mL) than in normotensive subjects (380 +/- 109 U/mL) or patients with renal disorders (393 +/- 115 U/mL) (P less than or equal to 0.004). The greater was the diastolic pressure in the hypertensive group, the greater was serum NAG activity (r = +0.30, P = 0.004). Hypertensive patients with high serum NAG activity were further characterized by a more exaggerated increase in systolic pressure (34 +/- 16 v 25 +/- 15 mm Hg, P = 0.051) and total peripheral resistance (19% +/- 18% v 12% +/- 13%, P = 0.042) in response to the cold pressor test and by a greater increase in systolic pressure (56 +/- 15 v 45 +/- 13 mm Hg, P = 0.009) and diastolic pressure (11 +/- 7 v 6 +/- 9, P = 0.043) in response to bicycle exercise testing than the group with low serum NAG activity. In contrast, urinary NAG activity tended to be only slightly higher in patients with essential hypertension than in the normotensive control group (33 +/- 31 v 23 +/- 29 U/mg creatinine [cr], P = 0.062), whereas patients with renal diseases had clearly increased urinary NAG activity (87 +/- 105 U/mg cr) (P less than 0.001). Following effective antihypertensive therapy, serum NAG activity decreased in patients with essential hypertension to values of normotensive control subjects (from 427 +/- 124 U/mL to 386 +/- 106 U/mL, P less than 0.01). A significant decrease in serum NAG activity was observed in patients with both initially high as well as low pretreatment serum NAG activities (P less than 0.001 and P less than 0.02, respectively). Urinary NAG activity overall was unchanged by antihypertensive treatment. We conclude that in patients with mild essential hypertension, serum NAG activity was already elevated (whereas urinary NAG activity was not) and was normalized by effective antihypertensive treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Acetylglucosaminidase↗

PubMed1990

When is discontinuation of antihypertensive therapy indicated?

Major advances have been established in the handling of hypertensive vascular disease in recent years. However, drug compliance, drug costs, and the side effects of antihypertensive agents have prompted the question of whether intermittent therapy or even possible removal of medication represents an alternative to life-long antihypertensive therapy. Several case reports, and controlled and uncontrolled studies, have focused on this subject, delivering promising but inconsistent results. In this review the attempt is made to clarify the controversial results in order to provide possible selection criteria for patients who can be assumed to benefit from the withdrawal of antihypertensive medication. In addition, the issue of whether a genuine hypertensive can ever become normal is critically reviewed, and an evaluation of the reported success rates is performed. Factors that predicted a successful withdrawal of medication were young age, normal body weight, low salt intake, low pretreatment blood pressure, successful therapy with one drug, and only minimal signs of target organ damage. Additional modification, such as a low-salt or a weight-loss diet, were demonstrated to extend the period of nonpharmacologic treatment. Nevertheless, further studies would be of great help in elucidating how long and how intensively hypertensive patients should be treated before the discontinuation of medication can be tested.

Antihypertensive Agents↗

PubMedDate not supplied

Male-to-female transmission of HIV in a cohort of hemophiliacs--frequency, risk factors and effect of sexual counseling.

The incidence of male-to-female transmission of HIV infection was studied in a population of 198 sexual partners of hemophiliacs who tested HIV positive since 1984. The follow-up observation period was 1987-1992. Transmission occurred in 20 (10%) cases. The analysis of risk factors for transmission was performed in a subgroup of 57 hemophiliacs with seronegative sexual partners as compared to eight transmitters. Transmitters showed a significantly more advanced immune depletion at enrollment as well as at the end of the observation period. Furthermore, transmitters had a more advanced disease at the end of the study (75% vs. 29% CDC IV; p < 0.01). Also virus cultures were more frequently positive in the transmitters than in the non-transmitters (71% vs. 42%). Regular sexual counseling was offered to all couples. After 1987, no new seroconversions were detected. However, two seroconversions in female partners of hemophiliacs outside the initial study population were observed. Both transmissions occurred during a period of severe clinical and immunological deterioration. This study shows that sexual partners of HIV-infected hemophiliacs with more advanced disease are at higher risk of infection with HIV. The frequency of male-to-female transmission of HIV in long-term monogamous sexual relationships practicing safer sex is low. Overall, disease awareness and counseling for safer sex seem to be effective in reducing transmission rates.

Adult↗

PubMedDate not supplied

Predicting in-hospital outcome in HIV-associated Pneumocystis carinii pneumonia.

Pneumocystis carinii pneumonia (PCP) in HIV-infected patients remains a life-threatening complication in the course of HIV infection. Despite effective treatment, mortality may still be as high as 10%. The identification of risk factors associated with a lethal outcome might be helpful as a guide to therapy for patients at risk and in the evaluation of new drugs with anti-pneumocystic activity. In a retrospective study 58 first episodes of HIV-associated PCP without prophylaxis were analyzed. Variables associated univariately with higher mortality were identified. A prognostic rule was established in a multivariate approach using canonical discriminant analysis. Cut-off values for parameters included were determined in order to allow a clinically applicable estimate of the individual risk. Variables associated with early mortality were hemoglobin, hematocrit, platelet count, albumin, total protein, gamma-globulins, and AaDO2. LDH values, percentage of neutrophils in the BAL, as well as the cellular immunologic state as indicated by CD4-cell count were not significantly associated with the outcome. The discriminant function yielded the best classification results with the inclusion of hemoglobin, albumin, and gamma-globulins (overall accuracy 86%). Two or more of the following parameters were associated with a 14-fold increased risk of in-hospital mortality: hemoglobin less than 10 g/dl, albumin less than 3 g/dl, and gamma-globulins less than 1.2 g/dl. This prognostic rule was 80% sensitive and 94% specific with a negative predictive value of 94%, yielding an overall accuracy of 91%. Patients with HIV-associated PCP with a positive prognostic rule have a 14-fold increased risk for in-hospital lethal outcome. This discriminant rule may be helpful in identifying patients at risk.

AIDS-Related Opportunistic Infections↗

PubMedDate not supplied

The probability of acquiring primary Toxoplasma infection in HIV-infected patients: results of an 8-year retrospective study.

There is much hope that HIV-infected patients and AIDS patients can reckon with a prolonged survival in future. The increased survival of AIDS patients with positive Toxoplasma serology is not necessarily associated with an increased risk of developing Toxoplasma encephalitis. For HIV-infected patients with negative Toxoplasma serology, the probability of acquiring a primary Toxoplasma infection in highly endemic areas such as Germany had not been studied to date. One hundred eighty-three HIV-infected patients were followed up between 1987 and 1995 in a retrospective study. Within the cohort, 95% of the patients were male and 83% haemophiliacs. The initial (1987) and final (1995) prevalence rate of Toxoplasma antibodies was 33.3% and 36.6%, respectively. The annual rise of the primary infection rate was calculated as 0.41%. The dye test was used for the detection of Toxoplasma-specific antibodies. This assay proved to be reliable and stable during long-term observation. The rate of primary toxoplasmosis found in this long-term study was not higher than that of pregnant women in Germany. Chemoprophylactic measurements for seronegative HIV-infected patients are therefore not recommended, but regular serological screening to detect seroconverters is.

AIDS-Related Opportunistic Infections↗

PubMedDate not supplied

Pathogenesis and pathophysiology of anemia in HIV infection.

Anemia occurs frequently among patients seropositive for human immunodeficiency virus (HIV), but its multifactorial origin complicates its differential diagnosis and adequate treatment. In addition, the etiology of anemia in HIV infection often remains unclear. In recent years several attempts have been undertaken to elucidate the mechanisms leading to HIV-associated anemia. Direct infection of erythroid progenitors has been discussed, but could not be proven. Furthermore, soluble factors like HIV proteins and cytokines have been suggested to inhibit growth of hematopietic cells in the bone marrow of HIV-infected patients. However, so far no statements can be made whether these factors are directly involved in myelosuppression or mediate their effect by inhibiting growth-factor synthesis. Opportunistic complications represent the underlying cause for anemia in a large number of HIV-infected patients. Next to this rather obvious reason for anemia, iatrogenic anemia induced by myelosuppressive drugs is also very common. It is of note, however, that modern dosages of < 600 mg zidovudine (ZDV) daily rarely cause anemia. Instead, other drugs that can induce anemia itself or by enhancing ZDV plasma concentrations must be considered important contributing factors. Deficiency of vitamin B12, folate and iron are frequently reported in HIV patients. However, specific investigations revealed appropriate storage amounts of these micronutrients. Supplementation may be beneficial in some patients, but often fails to reverse anemia in this population. In anemic HIV patients reticulocytopenia is a consistent finding. Additionally, inadequately low endogenous erythropoietin concentrations have been repeatedly reported. Thus, it is speculated that a blunted erythropoietin feedback mechanism contributes substantially to the pathogenesis of anemia in HIV patients.

Anemia↗

PubMedDate not supplied

Discontinuation of antihypertensive therapy: prevalence of relapses and predictors of successful withdrawal in a hypertensive community.

Antihypertensive therapy has been thought to be a life-long treatment. Nevertheless, antihypertensive medication may be discontinued in a substantial proportion of hypertensive patients at least for some time. The current study focused on predictors for the development of elevated blood pressure levels after discontinuation of antihypertensive drug therapy. In an open, prospective study, 88 white male patients with newly discovered essential hypertension (age 42 +/- 7 years) were tested at baseline. Blood pressure was measured in various situations (at work, at rest, before and during treatment, and at follow-up), and the hemodynamic profile at rest and cardiovascular response patterns during stress tests were evaluated. Left ventricular mass and other cardiovascular risk factors were also carefully determined. After 6 months of strict blood pressure control (< 140/90 mm Hg), they were treated by their primary care physician (mean duration of antihypertensive therapy 1.3 +/- 1.7 years). After 6 years, 37 patients were still on antihypertensive therapy, but 19 of the 37 had blood pressure values > or = 160/95 mm Hg. In 51 patients, therapy was discontinued: 29 were hypertensive, 15 were borderline hypertensive and 7 were normotensive. Relapse of hypertensive blood pressure in these 51 patients off therapy was predicted by resting blood pressure values before therapy (138 +/- 11/91 +/- 5 vs. 131 +/- 11/85 +/- 7 mm Hg, p < 0.05/0.01), cardiac output at rest (7.5 +/- 1.9 vs. 6.2 +/- 2.1 l/min, p < 0.05), total peripheral resistance (20 +/- 9 vs. 14 +/- 4 U, p < 0.05), increased heart rate during ergometry (50 +/- 8 vs. 44 +/- 6 b.p.m., p < 0.05) and left ventricular mass determined by echocardiography (212 +/- 60 vs. 189 +/- 44 g, p < 0.01). There was no difference in age, blood pressure levels before and during treatment, the number of consultations with the primary care physician or cardiovascular risk factor profiles. In conclusion, intermittent rather than life-long antihypertensive treatment may be possible in hypertensive patients with low resting blood pressure, high cardiac output, low total peripheral resistance and low left ventricular mass.

Adult↗