Biomedical subjects

H G Tiselius

Publications and source records attributed to H G Tiselius.

At least 73 records · Page 4Linked to original sources

PubMed1990

How are urine composition and stone disease affected by therapeutic measures at an outpatient stone clinic?

Urine composition in terms of calcium oxalate (CaOx) supersaturation was studied in 802 patients with calcium stone disease before any intervention and during follow-up. Supersaturation was expressed as the AP(CaOx) index, a simplified estimate of the ion activity product of CaOx, and a similar index calculated for a 24-hour urine volume of 1.5 liters the AP(CaOx) index(s). The AP(CaOx) index was significantly reduced in men with and without medical treatment who remained stone-free during follow-up (p less than 0.001), but not in men who continued to form stones. For the AP(CaOx) index(s), a significant reduction was observed only in patients on medical treatment without new stone formation (p less than 0.01). In women, significantly lower AP(CaOx) index values were recorded in recurrent as well as non-recurrent stone formers on medical treatment, whereas in the group without medical treatment and without recurrences the difference did not reach a statistically significant level. This was similar to the effect on the AP(CaOx) index(s) in non-recurrent women with medical treatment. The small number of women with recurrences might have influenced the result. Significantly reduced levels of the AP(CaOx) index were recorded for patients given thiazide, thiazide + magnesium, magnesium, and alkaline citrate. The AP(CaOx) index(s) was reduced in patients given thiazide + magnesium, magnesium, and alkaline citrate. Comparison between the effects on urine composition and clinical response showed that the reduced CaOx supersaturation observed with thiazide, thiazide + magnesium, and alkaline citrate, corresponded to a low rate of stone formation during follow-up. The inefficiency of allopurinol and orthophosphate in affecting urine supersaturation was reflected in a higher recurrence rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Allopurinol↗

PubMed1990

Evaluation of a system for classification of stones and their sites in kidneys treated with extracorporeal shock wave lithotripsy.

The results of treatment with extracorporeal shock wave lithotripsy (ESWL) were recorded in 1067 patients with renal calculi during their first admission to hospital. All treatments were performed in an unmodified Dornier HM3 lithotripter according to the original recommendations whereby the generator voltage was usually set between 18 and 23 kV. The stones in kidneys treated with ESWL alone were first classified into four different types (A. B. C. D) and after which a further subgrouping was carried out according to the number and sites of stones in the renal pelvis or calyces. The number of shock-waves. the energy index. the duration of treatment, and length of hospital stay as well as the therapeutic results after four weeks and six months were recorded for the different subgroups. An approximate estimate of the stone volume was calculated from measurements on a plain abdominal radiograph. The mean stone volume, number of shock waves, energy index, duration of treatment, and length of hospital stay increased progressively and significantly from group A to group D. The stone volumes and the energy indexes in the different subgroups within each type were distributed around levels that clearly differed between the types. Although minor variations were observed similar patterns also were recorded for the retreatment rate, the total duration of treatment, and the length of hospital stay. The therapeutic result, expressed as satisfactory disintegration, showed roughly similar results within each group but, as expected, the success rate decreased when more complicated stones were treated. Although stones located in the renal pelvis were often bigger than calyceal stones, the former seemed to disintegrate more easily.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation Studies as Topic↗

PubMed1990

Extracorporeal shock-wave lithotripsy of bile-duct stones. Initial Swedish experience.

Fifteen patients with mean age 74 (range 34-94) years were treated with extracorporeal shock-wave lithotripsy (ESWL) for bile-duct stones (intrahepatic in 4 cases) following failure of surgical or endoscopic treatment. A Dornier HM3 lithotriptor was used, and in all cases the ESWL session was preceded by establishment of external biliary drainage (endoscopic nasobiliary in 9, percutaneous transhepatic in 2 and a surgical T-tube in 4 cases) for radiologic positioning of stone. Endoscopic (14 cases) or surgical (1 case) sphincterotomy was done to facilitate spontaneous passage or endoscopic removal of fragments after ESWL. General anesthesia was not needed during the average 50 (range 25-65) min required for performance of ESWL. The number of delivered discharges was 750 to 2,100 and the generator voltage varied from 14 to 17 kV. Disintegration of stone was good in 12 cases and partial in two. Ten patients remain stone-free, five after spontaneous passage, and five after endoscopic extraction of fragments. There were few complications. ESWL may be useful in high-risk patients with failed endoscopic treatment of bile-duct stones and for management of intrahepatic stones.

Adult↗

PubMed1989

The effects of citrate on hydroxyapatite induced calcium oxalate crystallization and on the formation of calcium phosphate crystals.

The addition of different amounts of hydroxyapatite crystals (HAP) to a solution, metastably supersaturated with respect to calcium oxalate (CaOx) resulted in heterogenous crystallization at seed concentrations exceeding 0.2 mmol/l. The induction period varied between 1 and more than 8 h with the shortest period for a seed concentration of 2 mmol/l. Addition to the system of 1 and 2% of whole urine and citrate in concentrations corresponding to approximately 1% of that found in normal urine inhibited the crystallization for as long as 4 h. In a system supersaturated with respect to calcium phosphate (CaP) the total number of crystals was markedly reduced by citrate concentrations exceeding 0.5 mmol/l. The fractions of medium sized and large crystals were sharply reduced and small crystals predominated at higher citrate concentrations. This might indicate effects of citrate on both crystal growth and crystal aggregation. We conclude that increased citrate concentrations during treatment with alkali leads to a significant inhibition of CaOx growth on HAP as well as to a prevention of the formation of large CaP crystals from solutions supersaturated with respect to CaP.

Calcium Oxalate↗

PubMed1989

Evaluation of extracorporeal shock wave lithotripsy without anesthesia using a Dornier HM3 lithotriptor without technical modifications.

In 210 patients with urolithiasis extracorporeal shock wave lithotripsy was performed without regional, general or infiltration anesthesia by means of a technically unmodified Dornier HM3 lithotriptor. The stone burden varied from small ureteral stones to complete staghorn stones. All patients were given premedication with pethidine and diazepam, and a lidocaine-prilocaine-containing cream was applied on the skin at the entry site of the shock wave. Energy usually varied between 14 and 16 kv. More than 90% of the patients reported the pain to be at most of moderate intensity and acceptable. Less than 3% found the treatment unpleasant. The results were compared to those obtained in 250 patients treated with anesthesia according to the original procedure, with a generator voltage of 18 to 23 kv. The number of extracorporeal shock wave lithotripsy sessions for ureteral and large stones was somewhat higher with the low energy method than with the original procedure. However, the therapeutic result in terms of renal units without stones after 4 weeks was similar to that recorded for patients treated with the anesthesia method. According to these promising results we believe that extracorporeal shock wave lithotripsy without anesthesia in an unmodified Dornier HM3 lithotriptor can be performed successfully in a majority of patients and is an attractive alternative to other technical modifications of the equipment.

Anesthesia↗

PubMed1989

Extracorporeal shock wave lithotripsy of stones in the mid ureter.

We treated successfully 16 patients with stones in the mid ureter, that is overlying the pelvic bone, in the prone position with a Dornier HM3 lithotriptor. The lithotriptor was equipped with the original reflector and generator system, and all treatments were performed with only surface anesthesia of the skin and premedication with pethidine chloride and diazepam. Between 1 and 3 sessions were necessary with up to 2,000 shock waves at each session. The generator voltage was varied between 14 and 18 kv. After completion of extracorporeal shock wave lithotripsy all patients became free of stones without ureteroscopy or transureteral manipulation except for a ureteral catheter and fluid irrigation during treatment.

Diazepam↗

PubMed1989

Are prophylactic antibiotics necessary during extracorporeal shockwave lithotripsy?

A randomised clinical study was carried out on patients admitted for ESWL treatment in order to establish the requirement for prophylactic treatment with antibiotics during this procedure. Patients with clinical signs of urinary tract infection, evidence of infectious stones or a positive urine culture were excluded. All other patients were consecutively randomised into 3 groups which were given either trimethoprim + sulphamethoxazole or mecillinam (Group A), methenamine hippurate (Group B), or no treatment at all (Group C). Evaluation with respect to clinical signs of infection was done immediately after the treatment and 4 weeks later. In addition, a urine culture was performed 2 weeks after ESWL, i.e. 1 week after completing treatment with antibiotics and methenamine hippurate. With respect to infectious complications there were no differences between Groups A and C, between Groups B and C or between Group A and B+C, whereas an unexplained slightly higher infectious rate was recorded for Group B compared with Group A. In all patients the occurrence of bacteriuria was low (6.7%) despite the fact that almost 30% of patients had a ureteric catheter during the ESWL procedure. Patients with ureteric catheters did not present with more infectious complications than those without. All patients had a bladder catheter during ESWL. It was concluded that prophylactic treatment with antibiotics during ESWL treatment is unnecessary in all situations where an infectious aetiology is unlikely.

Adult↗

PubMed1989

Standardized estimate of the ion activity product of calcium oxalate in urine from renal stone formers.

An estimate of the ion activity product of calcium oxalate [AP(CaOx) index(s)] was calculated for a standardized 24-hour urine volume of 1,500 ml. AP(CaOx) index(s) was higher in stone formers than in normal subjects and higher in men than women. There was a good correlation between AP(CaOx) index(s) and our previously described CaOx risk index. AP(CaOx) index(s) might be particularly useful for comparison of different groups of patients as well as for comparison of men and women. It can be assumed that such an index will be very useful for evaluation of patients with short-term urine collections.

Calcium Oxalate↗

PubMed1989

Stone formation and urine composition in calcium stone formers without medical treatment.

A retrospective estimate of the annual rate of stone formation (fSF) was obtained in only 154 (35%) of 438 patients without medical treatment at our out-patient stone clinic. Eighty-three of these patients had never been on any prophylactic treatment and were only given advice concerning drinking and dietary habits. There was a high calcium excretion in 46%, high oxalate in 17%, low citrate in 11%, low magnesium in 17%, and increased urate in 16% of the patients. As much as 25% had a 24-hour urine volume below 1,000 ml. There was a good correspondence between stone formation during the follow-up period (tT) and a period of the same length following diagnosis (tA). The mean (+/- SD) tT was 3.2 +/- 1.9 years, with an fSF of 0.19 +/- 0.43. During the tA period fSF was 0.13 +/- 0.31. The number of patients who formed new stones during these periods were 21 and 22, respectively. It is suggested that stone formation during tT and tA advantageously might be used for preliminary evaluation of the therapeutic response. The risk of forming a urine highly supersaturated with calcium oxalate was expressed in terms of a standardized AP(CaOx) index calculated for a 24-hour urine volume of 1,500 ml. There was no relationship between this AP(CaOx) index and fSF. When only those patients were considered who formed new stones during the first 10 years after diagnosis, slightly higher values of the standardized AP(CaOx) index were recorded than in the recurrence-free group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989