Quantitative determination of brush-border enzyme excretion in the 24-hour urine is a much more sensitive index of renal tubular damage after aortography and selective renal arteriography than the conventional renal function tests such as serum creatinine and clearance determinations. Among the five brush-border enzymes which we investigated, alkaline phosphatase (AP) was the most sensitive diagnostic pointer. In 90% of hypertensive patients without detectable pre-existing renal parenchymal damage, abnormal levels of AP excretion in the urine were found on the same day as or on the day after the intra-arterial injection of contrast medium. Measurement of other brush-border enzymes does not provide any further diagnostic information. Provided there is no pre-existing renal parenchymal damage, the lesion caused by the contrast medium is transient and is usually reversed within 48 h. For the early detection of tubular lesions caused by tri-iodinated benzoic acid derivatives, AP excretion in the 24-hour urine should be measured at least twice – on the day of the contrast medium injection and on the following day.

Extracorporal detoxication methods in newborns are most unavailable, contraindicated because of technical problems. Herein are reported the experiences with a blood pump unit that was miniaturized for hemodialysis, hemofiltration, and plasmapheresis in newborns. In three premature infants with acute renal failure of different etiology (two newborns with severe Rh-erythroblastosis, 1 premature infant with hypoproteinemia) 13 single-needle hemofiltrations and 6 single-needle plasmaphereses were performed with double head pump, special tube systems, and small modules. The age of the patients ranged from 1 to 14 days, body weight was between 800 and 2,800 g. Four umbilical veins and two femoral veins were used as vascular access. The ultrafiltration rate during the treatment averaged 0.3 mumin in single-needle hemofiltration and the plasma filtrate flow rate 1.3 mllmin in single-needle plasmapheresis. All treatments were well tolerated. Four patients died due to complications unrelated to the treatment, two patients recovered. These preliminary results show that both hemofiltration and plasmapheresis may be carried out without major problems in premature infants and newborns.

A more concentrated desmopressin (DDAVP) preparation (40 µg/ml), which required small injection volumes (< 1 ml), was studied in a double-blind trial in 10 healthy volunteers, 12 patients with haemophilia A, and 8 patients with uraemic bleeding. DDAVP was administered by subcutaneous injection at a dose of 0.4 µg/kg body weight. In healthy subjects, peak levels of DDAVP ranging from 480 to 638 pg/ml were reached 1 h after the subcutaneous injection and DDAVP was eliminated with a mean half-life of 3.1 h. DDAVP produced a 2.5-fold (3.0-fold) increase of factor VIII·C (factor VIII·Ag) and a 1.9-fold (2.2-fold) increase of von Willebrand factor:Ag (ristocetin cofactor) over baseline levels. Additionally, a 2.1-fold increase of tissue-type plasminogen activator antigen was observed. Factor VIII and von Willebrand factor were rapidly eliminated with a half-life ranging from 1.3 to 5.7 h and from 1.1 to 11.4 h, respectively. In haemophilia A patients, DDAVP produced a 2.3-fold increase of factor VIII·C 1 h after the injection. DDAVP was given on 8 occasions for management of bleeding, and only in 1 patient did a wound haematoma (after herniotomia) occur. In 7 of the 8 patients with uraemia the bleeding time shortened, and in all patients an increase of platelet retention and a decrease of platelet count was observed (p < 0.05). No serious local or systemic untoward side effects were observed.

Two patients suffering from allergic bronchial asthma who showed no improvement despite six and four weeks, respectively, of drug therapy were successfully treated with therapeutic plasma exchange. The first patient had no attacks over a period of five months, and the other patient had none for over one year. Although this report only deals with single observations, we believe that therapeutic plasma exchange is of particular value for patients with severe allergic bronchial asthma because it eliminates in addition to immunocomplexes other substances, including antigens, rapidly from the blood. This means that it is possible to directly intervene in the pathomechanism. However, further investigations are necessary in order to corroborate this successful therapy.

Substitution solutions used for plasmapheresis (PH) may be human albumin, serum protein conserves or plasma. 746 plasmapheresis carried out on 88 patients with a variety of diseases were examined and the side effects due to the substitution solutions were investigated. Side effects occurred in less than 10% of the cases where the four substitution solutions were used. The least side effects were observed in treatments using human albumin as substitution. Side effects increased for serum protein conserves, followed lyophilised plasma and were highest for fresh frozen plasma. In view of these possible side effects the criteria for PH should be strictly observed and the substitution solution should meet clinical requirements.