Biomedical subjects

A L Zanen

Publications and source records attributed to A L Zanen.

8 recordsLinked to original sources

PubMed2002

[Severe hypokalemia with paralysis in a patient with distal renal tubular acidosis as an initial expression of Sjögren's syndrome].

In a 33-year-old woman with a recent flaccid paralysis of the arms and legs, laboratory tests demonstrated a severe hypokalemia with hyperchloremic metabolic acidosis and abnormally acidified urine. The urinary anion gap was positive in the presence of acidosis, thus establishing the diagnosis of distal renal tubular acidosis. The patient made a full recovery after potassium and alkali replacement. Further investigation revealed Sjögren's syndrome as the underlying cause.

Acid-Base Equilibrium↗

PubMed2001

Flow measurements in dialysis shunts: lack of agreement between conventional Doppler, CVI-Q, and ultrasound dilution.

BACKGROUND: Measuring flow in dialysis shunts is recommended to predict imminent thrombosis. Multiple methods for measuring blood flow are in use. Numerous ultrasound protocols exist which determine volume flow using a conventional Doppler (CD) frequency shift analysis technique. All of these are subject to potentially large errors. Quantitative colour velocity index (CVI-Q) does not make use of the Doppler equation and is more precise in vitro. Ultrasound dilution (UD) measures access flow during dialysis in a non-operator-dependent way. The aim of the present study was to compare these three methods of measuring access flow in vivo for agreement with each other. METHODS: In 38 accesses flow was measured by CD, CVI-Q, and UD. All measurements were done during dialysis. Agreement was determined by intraclass correlation coefficient (ICC=R(i)) and Bland-Altman analysis. RESULTS: ICC between UD and CVI-Q was R(i)=0.56. ICC between UD and CD was R(i)=0.10, and ICC between CD and CVI-Q was R(i)=0.16. Bland-Altman analysis revealed a bias (mean difference) of -38 ml/min between UD and CVI-Q, a bias of 1129 ml/min between UD and CD, and a bias of 1167 ml/min between CVI-Q and CD. CONCLUSIONS: CD measurements did not agree with UD or CVI-Q much higher values were recorded with the former than with the latter two techniques. The agreement between UD and CVI-Q measurements is low but reasonable. Caution must be applied in comparing and interpreting values of access flow measured by different techniques.

Adult↗

PubMed2000

Reversible renal failure after treatment with omeprazole.

Omeprazole is a proton pump inhibitor widely used in the treatment of gastro-esophageal reflux disease and peptic ulcer disease. In a 73-year-old man we describe renal failure due to acute interstitial nephritis after use of omeprazol during 4 months. Unexpected renal failure without signs of hydronephrosis should always provoke awareness of drug reaction, omeprazole being one of the possible drugs.

Acute Kidney Injury↗

PubMed1996

'Oversaturation' of transferrin after intravenous ferric gluconate (Ferrlecit(R)) in haemodialysis patients.

BACKGROUND: Chronic haemodialysis causes blood loss and iron-deficiency. This can be corrected with intravenous preparations, e.g. sodium ferric-gluconate (FeGl). In two patents complaints of hypotension and malaise during FeGl infusion coincided with high levels of serum iron and a calculated transferrin iron saturation above 100%. Iron toxicity could be the cause of these complaints. Free iron is known to aggravate the toxicity of free radicals and other reactive oxygen products that are constantly formed in the body. We compared four rates of FeGl infusion with regard to iron parameters. METHODS: 20 dialysis patients received a total of 26 infusions of FeGl. A rapid infusion of 135 mg (Protocol A (n=10)) or 62.5 mg (Protocol B (n=7)) of FeGl was given during the last 30 min of dialysis. A slow infusion of 125 mg (Protocol C (n=9)) or 62.5 mg (Protocol D (n=10)) was given during 4 or 4.5 h of dialysis. Blood was taken at regular intervals, before, during, and after dialysis for determination of serum iron, transferrin, ferritin, haematocrit, total protein, albumin, and lactate dehydrogenase (LDH). Transferrin saturation was calculated from transferrin and serum iron. RESULTS: With rapid infusion A (125 mg) the highest levels of serum iron (median 120 (range 40-159) micromol/l) and transferrin saturation (207 (84-331)%) were seen at the end of the infusion. These were significantly higher than the peak levels with B, C, and D (P</=0.03). With rapid infusion B (62.5 mg), peak levels were intermediately high (serum iron 61 (50-96) micromol/l; transferrin saturation 118 (91-174)%). With slow infusion C (125 mg) similar peak levels were seen (serum iron 83 (43-106) micromol/l; transferrin saturation 141 (88-172)%). With slow infusion D (62.5 mg), the lowest peak levels were seen (serum iron 38 (31-55) micromol/l; transferrin saturation 78 (43-92)%). These levels were significantly lower than those with A, B and C (P<=0.002). Only with D all patients showed a transferrin saturation lower than 100%. Ferritin was increased before the next dialysis in all patients. LDH was not significantly elevated during any infusion. CONCLUSIONS: The commonly used rapid infusion rate (A) of FeGl causes 'oversaturation' of transferrin. This is compatible with iron toxicity due to free iron which may explain our patients' complaints. Free iron cannot be measured directly. LDH as a crude measure of cell damage was not elevated. Better measurements to prove free iron toxicity, like lipid peroxides, are not yet readily available. Infusion during a longer period at a lower dose (D) is effective and eliminates 'Oversaturation' of transferrin and probably the danger of iron toxicity.

Adult↗

PubMed1995

Pancreatic pseudocyst as a cause of upper gastrointestinal bleeding.

A 67-year-old man with a history of an attack of pancreatitis was repeatedly investigated for recurrent gastrointestinal bleeding necessitating blood transfusions. Routine investigations did not reveal the source of bleeding. Repeated angiograms also were not diagnostic. A hot spot identified on a 99mTc-pertechnate-labelled erythrocyte scan prompted an endoscopic retrograde cholangio-pancreatography (ERCP), which showed bleeding through the papilla of Vater. The source of bleeding appeared to be a small pancreatic pseudocyst. The patient was treated with a duodenopancreatectomy in which the pylorus was preserved. No rebleeding occurred since the operation. Pancreatic pseudocysts must be considered as a source of upper gastrointestinal bleeding in patients with bleeding of "obscure" origin. 99mTc-pertechnate-labelled erythrocyte scanning and ERCP may be helpful, even when angiography is normal.

Aged↗

PubMed1995

Bleeding into a liver cyst can be treated conservatively.

OBJECTIVE: To report the case of a patient with haemorrhage in a large hepatic cyst. PATIENT: A 66-year-old man, who presented with right shoulder pain and subsequent sudden abdominal pain. A large hepatic cyst containing blood was found at ultrasonography. INTERVENTIONS: The patient was treated conservatively. RESULTS: The patient's symptoms resolved quickly. No symptoms or complications recurred during a follow-up of 2 years. CONCLUSION: Therapy for non-parasitic liver cysts is indicated when symptoms or complications related to the cysts occur. This case shows that spontaneous haemorrhage into a non-parasitic hepatic cyst may follow a benign course and may be treated conservatively.

Aged↗

PubMed1994

Cholesterol-embolism: diagnosis by endoscopy.

A case report is presented, concerning a 68-year-old woman, with gastro-intestinal complaints, six weeks after an aortic arteriography. On gastroscopy a duodenal ulcer was found and multiple purple discolourations. Biopsies show that these discolourations were caused by cholesterol-emboli. As the patient's complaints resided quickly after treatment for duodenal ulcer, the cholesterol-emboli can be seen as incidental findings. The gastroscopical biopsies were an important clue to the diagnosis of the cause of the rapid progressive renal failure in this patient.

Acute Kidney Injury↗

PubMed1993

Inhalation trauma due to overheating in a microwave oven.

The microwave oven is a kitchen appliance that has become increasingly popular in recent years. In some instances the temperature in the microwave oven can become exceedingly high. A case is discussed of a patient with respiratory distress after inhalation of gas from an overheated microwave oven.

Adult↗