PubMed Health⌕ Search

Biomedical subjects

A J van der Ven

Publications and source records attributed to A J van der Ven.

At least 19 recordsLinked to original sources
PubMed2002

Catheter-related epidural abscesses -- don't wait for neurological deficits.

Epidural abscess is a rare but serious complication of epidural anesthesia for peri- and postoperative analgesia. It is feared because of possible persistent neurological deficits. Epidural abscess presents mostly with a classic triad of symptoms: back pain, fever and variable neurological signs and symptoms. When neurologic signs or symptoms develop, MRI scanning is the diagnostic procedure of choice. The therapy of choice is intravenous antibiotics for more than 4 weeks with or without a laminectomy or drainage. In the present paper we describe three patients with epidural abscesses presented during a time period of 1 year in our hospital. In each case, patients developed local signs of infection and systemic signs, but no neurological symptoms. Based on these cases and a review of the literature, we propose that MRI scanning should be strongly considered when patients present with systemic and local signs, even in the absence of neurological deficits.

Abscess↗
PubMed2001

[HIV-positive drug users in South Limburg: number and characteristics, a capture-recapture analysis].

OBJECTIVE: To estimate the number of HIV positive drug abusers (HDs) in South Limburg, the Netherlands, and to ascertain the characteristics of this group, so that special HIV healthcare can be planned. DESIGN: Capture-recapture analysis. METHOD: Capture-recapture analysis was carried out and abuser characteristics were determined using three incomplete, partially overlapping registers of HDs from the regional AIDS hospital, the Regional Institute for Addiction and the Municipal Health Service Centres in South Limburg. RESULTS: From the 80 HDs included, the Municipal Health Service Centres observed 59 HDs, the Institute for Addiction 45 and the hospital 44. The capture-recapture analysis gave an estimate of 110 HDs (95% CI: 91-164) in South Limburg. Assuming 1100 drug users in South Limburg of which 76% had injected on one or more occasions, the HIV prevalence among injecting drug users was estimated at 13% (110/836). From the observed HDs 80% were male, with a mean age of 38 years (SD: 7) and a mean age at the onset of drug use of 18 years (SD: 5). All HDs currently injected or had previously injected. The first injected drugs were used at a mean age of 21 years (SD: 6). All HDs used heroine, 84% also used cocaine, 54% were homeless, 91% unemployed and 80% had a history of imprisonment. Further, 71% of the female HDs were prostitutes, 37% of the male ones visited prostitutes, 81% had contracted hepatitis B (of which 20% were a carrier) and all HDs were infected with hepatitis C. An estimate based on prevalence data gave 143/836 (17%) and that based on capture-recapture analysis with two registrations was 102/836 (12%). CONCLUSION: The number of HDs was estimated to be 110. The population had a marginalized existence and there was a risk of HIV spreading.

Adult↗
PubMed2001

Clinical value of bacteriological examinations of nasal and paranasal mucosa in patients with chronic sinusitis.

Although many investigations on the bacteriology of chronic sinusitis have been reported, there is still much discussion about the physiological flora of the nose and paranasal sinuses, the role of the various aerobic and anaerobic "pathogenic" bacteria, and the influence of the anatomical location from which samples for bacteriology are taken. We conducted a qualitative and semi-quantitative bacteriological examination of patients with chronic sinusitis undergoing a transnasal sinus operation (patient group), and of patients without chronic sinusitis undergoing a septoplasty (control group). In both groups brush smears of the inferior nasal turbinate and biopsies of the middle nasal turbinate were taken, with additional biopsies of the maxillary sinus and ethmoidal bulla in the chronic sinusitis group. In both groups coagulase-negative staphylococci were identified in almost all samples. Staphylococcus aureus was found in 22% (middle turbinate) to 33% (inferior turbinate) of the samples from the control group and in 33% (maxillary sinus, middle turbinate) to 50% (inferior turbinate) of the samples from the patient group. Other (pathogenic) aerobic bacteria were found much more rarely and only slight distinctions between control and patient group were observed. The concentrations of the different bacterial species (colony-forming units) were comparable in both groups. Strictly anaerobic bacteria and fungi were not identified. Only small discrepancies between the various methods and/or locations of sampling were found. Based on our bacteriological findings a differentiation between patients with and without chronic sinusitis was not possible. These results shed doubt on the clinical value of bacteriological examinations of nasal and paranasal mucosa in patients with chronic sinusitis.

Adolescent↗
PubMed2001

Resolution of infectious parameters after antimicrobial therapy in patients with ventilator-associated pneumonia.

Although recommended durations of antimicrobial therapy for ventilator-associated pneumonia (VAP) range from 7 to 21 d, these are not based on prospective studies and little is known about the resolution of symptoms after start of antibiotics. Resolution of these symptoms was investigated in 27 patients. VAP was diagnosed on clinical, radiographic, and microbiological criteria, including quantitative cultures of bronchoalveolar lavage. All patients received appropriate antibiotic therapy. Highest temperatures, leukocyte counts, Pa(O(2))/FI(O(2)) ratios, and semiquantitative cultures of endotracheal aspirates were recorded from start of therapy until Day 14. Resolution was defined as the first day that these parameters fulfilled the following definition: temperature < or = 38 degrees C, leukocytes < or = 10 x 10(9)/L, Pa(O(2))/FI(O(2)) ratio > or = 25 kPa, and no or +1 of bacterial growth of etiologic pathogens in cultures of endotracheal aspirate. VAP was caused by Enterobacteriaceae (n = 14), P. aeruginosa (n = 7), S. aureus (n = 6), H. influenzae (n = 3), and S. pneumoniae (n = 1). H. influenzae and S. pneumoniae were eradicated from tracheal aspirates, whereas Enterobacteriaceae, S. aureus, and P. aeruginosa persisted, despite in vitro susceptibility to antibiotics administered. Significant improvements were observed for all clinical parameters, most apparently within the first 6 d after start of antibiotics. Newly acquired colonization, especially with P. aeruginosa and Enterobacteriaceae, occurred in the second week of therapy. Six patients developed a recurrent episode of VAP, four of them with P. aeruginosa. Clinical responses to therapy for VAP occur within the first 6 d of therapy, endotracheal colonization with Gram-negative bacteria persists despite susceptibility to therapy, and acquired colonization usually occurs in the second week of therapy and frequently precedes a recurrent episode.

Adult↗
PubMed1999

Swelling of hand and forearm caused by Mycobacterium bovis.

A 75-year-old native Dutch farmer presented with a painless swelling of his right hand extending into his forearm, accompanied by general malaise and low grade fever. His medical history revealed coxitis tuberculosa in 1954 and injury of the same hand in 1978. His present swelling appeared to be caused by Mycobacterium bovis, probably due to endogenous reactivation. Whether the mycobacteria reached the hand hematogenously or were directly inoculated at the time of injury of his hand in 1978 remains unclear.

Aged↗
PubMed1999

Detection of non-infectious conditions mimicking pneumonia in the intensive care setting: usefulness of bronchoalveolar fluid cytology.

The present study investigated the usefulness of bronchoalveolar (BAL) fluid cytology in the identification of non-infectious pulmonary conditions in patients hospitalized in the intensive care unit (ICU) and suspected of pneumonia. A total of 182 BAL fluid samples obtained during a 27-month period from 130 ICU patients with suspected pneumonia were quantitatively cultured and investigated for opportunistic pathogens. Cytocentrifuged preparations stained with the May-Grünwald Giemsa and Perls's methods were reviewed. A non-infectious aetiology was considered when cultures yielded micro-organisms in quantities < 10(3) colony-forming units (CFU) per ml, in the absence of any other pathogen and in conjunction with one or more of the following cytological findings: > 20% haemosiderin macrophages, > 10% lymphocytes, the presence of activated lymphocytes, plasma cells, > 5% eosinophils, a preponderance of foamy macrophages, reactive type II pneumocytes or malignant cells. Patients' clinical records were reviewed to identify a clinical diagnosis for these episodes. In thirty-five (19.2%) BAL fluid samples from 26 patients, the cytological findings pointed to a non-infectious origin. An alternative diagnosis was ascertained in 20 of 26 patients. Diagnoses included: drug-induced pneumonitis (n = 7), aspiration of gastric contents (n = 2), pulmonary emboli (n = 3), adult respiratory distress syndrome (n = 4), lung contusion (n = 1), cardiogenic pulmonary oedema (n = 1), and carcinomatous lymphangitis (n = 2). The BAL fluid cytological findings were readily discernable and proved to be useful in the diagnostic work-up of samples obtained from ICU patients with suspected pneumonia.

Adult↗
PubMed1999

Antimicrobial resistance patterns in urinary isolates from nursing home residents. Fifteen years of data reviewed.

The antibiotic resistance patterns of gram-negative bacteria isolated from nursing home patients between 1983 and 1997 were analysed. Escherichia coli was the most prevalent isolate (48%) followed by Proteus spp. (26%) and other Enterobacteriaceae (20%). During the study period, the susceptibility of E. coli decreased for co-trimoxazole (79% to 62%), increased for nitrofurantoin (79% to 91%) and remained unchanged for amoxycillin (41%). Susceptibility to norfloxacin, available from 1990, decreased from 87% to 71%. Similar trends were observed when the susceptibilities of all gram-negative urinary pathogens were combined. The changes in susceptibility can probably be attributed to the empirical prescribing practices in the nursing homes studied.

Anti-Bacterial Agents↗
PubMed1999

Clinical consequences of the biphasic elimination kinetics for the diuretic effect of furosemide and its acyl glucuronide in humans.

This review discusses the possibility of whether furosemide acyl glucuronide, a metabolite of furosemide, contributes to the clinical effect of diuresis. First an analytical method (e.g. HPLC) must be available to measure both parent drug and furosemide acyl glucuronide. Then, with correctly treated plasma and urine samples (light protected, pH 5) from volunteers and furosemide-treated patients, the kinetic curves of both furosemide as well as its acyl glucuronide can be measured. The acyl glucuronide is formed in part by the kidney tubules and it is possible that the compound is pharmacologically active through inhibition of the Na+/2Cl-/K+ co-transport system; up to now the mechanism of action has been solely attributed to furosemide. The total body clearance of furosemide occurs by hepatic and renal glucuronidation (50%) and by renal excretion (50%). Enterohepatic cycling of furosemide acyl glucuronide, followed by hydrolysis, results in a second and slow elimination phase with a half-life of 20-30 h. This slow elimination phase coincides with a pharmacodynamic rebound phase of urine retention. After each dosage of furosemide, there is first a short stimulation of urine flow (4 h), which is followed by a 3-day recovery period of the body. The following clinical implications arise from study of the elimination kinetics of furosemide. Repetitive dosing must result in accumulation of the recovery period. Accumulation of furosemide and its acyl glucuronide in patients with end-stage renal failure results from infinite hepatic cycling. Impaired kidney function may result in impaired glucuronidation and diuresis. While kidney impairment normally requires a dose reduction for those compounds which are mainly eliminated by renal excretion, for diuretics, a dose increment is required in order to maintain a required level of diuresis. The full clinical impact of the accumulation of furosemide and its acyl glucuronide in patients with end-stage renal failure has to be determined.

Chromatography, High Pressure Liquid↗
PubMed1998

[Acute disorders of intestinal perfusion; a nonrigid abdomen may still be acute].

Three patients, a man aged 50 years and two women aged 46 and 45 years, with abdominal pains and an undistended abdomen, were found to have acute mesenteric ischaemia. The causes were: unknown, a thrombus in the descending aorta and severe atherosclerosis, respectively. In the male patient, only 30 cm of vital small intestine ultimately remained; in one woman embolectomy sufficed, in the other, resection of a limited portion of the jejunal tract. All three patients fully recovered. Acute mesenteric ischaemia is a potentially lethal disease. Diagnosis in the first reversible phase makes full recovery of the intestine possible. This may be difficult since the clinical signs and symptoms are not specific in this phase and invasive diagnostic procedures (angiography) are required for accurate diagnosis. By making an angiogram of the mesenteric vessels in each patient with severe abdominal pain, no signs of peritonitis and leukocytosis, without another diagnosis, reversible mesenteric ischaemia can be diagnosed and a vascular surgical reconstruction can be planned.

Abdomen, Acute↗
PubMed1998

Glutathione homeostasis is disturbed in CD4-positive lymphocytes of HIV-seropositive individuals.

BACKGROUND: Numerous in vitro tests have suggested that a disturbed cellular glutathione homeostasis plays an important role in the pathogenesis of human immunodeficiency virus (HIV) infection. METHODS: Using validated high-performance liquid chromatography (HPLC) methods, glutathione concentrations were determined in plasma and in cytosol of CD4+ lymphocytes and CD14+ cells of HIV-seropositive individuals and healthy control subjects. We measured concentrations of total glutathione, which is the sum of reduced (GSH) and oxidised (GSSG) glutathione and mixed disulphides of which there are two fractions: soluble mixed disulphides (GSSR) and protein bound glutathione (ProSSG). Also, non-protein-bound glutathione was measured, which is the sum of GSH, GSSG and GSSR. Thirty-five healthy control subjects and 35 HIV-infected individuals participated in the study. RESULTS: We found that in CD4+ lymphocytes from HIV-seropositive individuals, total glutathione levels were significantly higher than in healthy control subjects, whereas the fraction of non-protein-bound glutathione was not different. This can only be explained by an increase in the protein-bound fraction of glutathione indicating the presence of oxidative stress in CD4+ lymphocytes of HIV-seropositive individuals. Glutathione measurements of cytosol of CD14+ cells and plasma were, however, not compatible with significant increased oxidation. Glutathione precursors (cysteine, cysteinylglycine, glutamylcysteine and homocysteine) and products of lipid peroxidation (thiobarbituric acid-reactive substances) were also measured in plasma and did not differ between healthy control subjects and HIV-seropositive individuals. CONCLUSION: We conclude that the glutathione homeostasis is disturbed in CD4+ lymphocytes of HIV-seropositive individuals. The glutathione redox dysbalance in CD4+ lymphocytes could be important in the pathogenesis of HIV infection and have implications for therapy.

Adult↗
PubMed1997

[Acute pulmonary histoplasmosis as an imported disease].

A previously healthy 44-year-old male traveller presented with a dry cough, fever and an abnormal chest X-ray after a stay in Guatemala, where he had explored bat caves. Acute pulmonary histoplasmosis was diagnosed after culture of Histoplasma capsulatum from bronchial washings. A favourable response was seen upon treatment with itraconazole for six weeks. Acute pulmonary histoplasmosis should be considered in a healthy traveller returning with fever from the USA or subtropical areas.

Adult↗
PubMed1997

Rapid disease progression in human immunodeficiency virus type 1-infected individuals with adverse reactions to trimethoprim-sulfamethoxazole prophylaxis.

We studied the relation between the occurrence of adverse reactions to trimethoprim-sulfamethoxazole (TMP-SMZ) prophylaxis and the subsequent course of human immunodeficiency virus (HIV) infection in a cohort of homosexual men. Adverse reactions to TMP-SMZ were associated with a more rapid progression to AIDS (P < .001) and death (P < .001) and with a more rapid decline in CD4+ cell counts (P = .001). The median time to progression to AIDS was 14.9 months in subjects with adverse reactions to TMP-SMZ and 32.5 months in those without adverse reactions. After exclusion of Pneumocystis carinii pneumonia (PCP) and toxoplasmosis from the case definition of AIDS, the differences in the rate of progression to AIDS between subjects with and without adverse reactions to TMP-SMZ were still highly significant (P = .004). A low CD4+ cell count at baseline and the use of antiretroviral agents before the start of prophylaxis were predictors of adverse reactions to TMP-SMZ but did not account for the difference in progression to AIDS between subjects with and without adverse reactions to TMP-SMZ. In a univariate analysis, the relative hazard of adverse reactions to TMP-SMZ for progression to AIDS was 2.54 (95% confidence interval [CI], 1.50-4.28); in a multivariate analysis, it was 2.21 (95% CI, 1.29-3.81). The relative hazards of adverse reactions to TMP-SMZ for progression to AIDS with the exclusion of PCP and toxoplasmosis, CD4+ cell counts of <50/mm3, and death were 2.16 (95% CI, 1.25-3.72), 2.37 (95% CI, 1.36-4.12), and 3.21 (95% CI, 1.80-5.72), respectively. It is unclear whether adverse reactions to TMP-SMZ induce or merely predict progression of HIV disease.

AIDS-Related Opportunistic Infections↗