Insulin clearance contributes to the variability of nocturnal insulin requirement in insulin-dependent diabetes mellitus.

We have previously described, in insulin-dependent diabetic subjects (IDDM), a small, but significant, increase in the insulin clearance rate (ICR) during 0600-0800 h as compared with 0100-0300 h. To determine whether this increase was also seen at more physiologic levels of insulin replacement, we calculated ICR during euglycemic clamp studies in 13 patients with IDDM with a constant infusion of insulin at 20 mU/min/m2 and during insulin replacement from the Biostator GCIIS without exogenous glucose. During the euglycemic clamp study with constant insulin infusion at 20 mU/min/m2, the ICR was 16% higher at 0600-0800 h than at 0100-0300 h (264 +/- 50 ml/min/m2 versus 228 +/- 51 ml/min/m2; P less than 0.005). During insulin replacement by the Biostator, the mean insulin infusion rate increased by 92 +/- 27% (7.5 +/- 1.1 to 13.5 +/- 1.2 mU/min/m2; P less than 0.001) and ICR increased by 123 +/- 30% (130 +/- 24 to 268 +/- 51 ml/min/m2; P less than 0.01) during the prebreakfast period when compared with 0100-0300 h. There was a highly significant correlation (r = 0.97) between the increment in insulin infusion rate and the increment in ICR. Measurement of insulin concentration in saline solutions, delivered by the Biostator at a same rate and under similar conditions to those in this study, showed that insulin delivery was stable for the 8-h period of this study.(ABSTRACT TRUNCATED AT 250 WORDS)

Inadvertent sulfonylurea-induced hypoglycemia. A dangerous, but preventable condition.

Two patients with severe hypoglycemia due to inadvertent use of oral hypoglycemic agents are described. Unintentional substitution of tablets with sulfonylurea drugs was related in both cases to a similarity in shape and color of the pills. In one case glyburide was interchanged with an artificial sweetener, while in the other case chlorpropamide was dispensed by a pharmacist instead of quinidine bisulfate. To our knowledge, 20 similar cases have been reported in the medical literature. Most of them were attributed to sound-alike trade names of drugs. Inadvertent sulfonylurea-induced hypoglycemia has to be included in the differential diagnosis of severe unexplained hypoglycemia. This dangerous condition can be prevented by instructing patients to carefully identify their drugs, introducing typed prescription forms using generic names, and avoiding similar names and appearance of pills.

Hyperammonemia complicating mesenteric vein thrombosis.

Hyperammonemic coma developed in a 69-year-old woman with prolonged symptoms of abdominal pain, dysphagia, and fever. At laparotomy for an acute condition within the abdomen, mesenteric vein thrombosis was found and partial intestinal resection was performed. Following surgery, the patient regained consciousness and blood ammonia levels became normal. Hyperammonemia and coma complicating mesenteric vein thrombosis have not yet been described. Venous shunts are suggested as being responsible for this rare complication.

Labetalol in the treatment of essential hypertension: a single-blind dose ranging study.

The hypotensive efficacy of labetalol was evaluated in 29 patients with essential hypertension in a single-blind dose ranging study. After a two-week period of placebo treatment, labetalol was given in oral doses of 0.6 g/d, 0.8 g/d, and 0.8 g/d combined with 25-50 mg/d of hydrochlorothiazide. Each regimen lasted four weeks. The decrease in blood pressure was dose dependent: 90% of patients showed a significant reduction in diastolic blood pressure and 75% showed a significant reduction in systolic blood pressure. In 69% of the patients, side effects of the drug were noted, and in five patients (17%), treatment was discontinued because of the side effects. Seven patients received labetalol intravenously before the oral treatment. Their heart rate and blood pressure reductions were similar to those found in patients only taking the medication orally. We conclude that labetalol is an efficient and safe antihypertensive agent in both oral and intravenous administration. However, the high incidence of side effects makes labetalol a drug of second choice in uncomplicated hypertensive patients.

The timing of relaparotomy and its influence on prognosis. A 10 year survey.

Review of 3,680 abdominal operations performed in our department during a 10 year period revealed that 95 patients (2.6 percent) required relaparotomy because of surgical complications during the same hospitalization. Of these, 37 patients died, a mortality of 38 percent, which is approximately 10-fold that for similar operations in which reintervention was not necessary. The mortality was greater in male patients and was very high (64 percent) in those over the age of 70 years. The most common complication necessitating relaparotomy was peritonitis (0.9 percent of the total series), followed by intestinal obstruction (0.8 percent) and wound disruption (0.7 percent). The frequency of bleeding requiring reoperation was low (0.1 percent). Intestinal operations were associated with the highest incidence of complications (6.2 percent), followed by gastric operations (4 percent). Assessment of the time interval between the development of the surgical complication and reoperation in each case indicated that there had been an unjustifiably long delay in reaching the correct diagnosis, in performing reoperation or both in 26 percent of this series (40 percent of the cases of peritonitis). This delay was usually greater with early than with relatively later complications. However, our findings failed to support a detrimental effect of this delay and even showed a tendency toward better results and a lower mortality when conservative treatment was prolonged before reoperation was performed.

Alterations in damage processes in dense cancellous bone following gamma-radiation sterilization.

Structurally intact cancellous bone allograft is an attractive tissue form because its high porosity can provide space for delivery of osteogenic factors and also allows for more rapid and complete in-growth of host tissues. Gamma radiation sterilization is commonly used in cancellous bone allograft to prevent disease transmission. Commonly used doses of gamma radiation sterilization (25-35 kGy) have been shown to modify cortical bone post-yield properties and crack propagation but have not been associated with changes in cancellous bone material properties. The purpose of this study was to determine the effects of irradiation on the elastic and yield properties and microscopic tissue damage processes in dense cancellous bone. Cancellous bone specimens (13 control, 14 irradiated to 30 kGy) from bovine proximal tibiae were tested in compression to 1.3% apparent strain and examined for microscopic tissue damage. The yield strain in irradiated specimens (0.93+/-0.11%, mean+/-SD) did not differ from that in control specimens (0.90+/-0.11%, p=0.44). No differences in elastic modulus were observed between groups after accounting for differences in bone volume fraction. However, irradiated specimens showed greater residual strain (p=0.01), increased number of microfractures (p=0.02), and reduced amounts of cross-hatching type damage (p<0.01). Although gamma radiation sterilization at commonly used dosing (30 kGy) does not modify elastic or yield properties of dense cancellous bone, it does cause modifications in damage processes, resulting in increased permanent deformation following isolated overloading.

Recurrent erythema nodosum, arthritis and IgA nephropathy.

Erythema nodosum and IgA nephropathy are nosologic entities with an immunologic background. IgA nephropathy is a specific disease of the kidneys, while erythema nodosum may be associated with other illnesses. We report a unique case in which intermittent hematuria due to IgA nephropathy was superimposed on recurrent attacks of erythema nodosum and arthritis. A common pathophysiology is suggested.

Renin, aldosterone, and serum-converting enzyme activity during normal and hypertensive pregnancy.

Plasma renin activity, plasma aldosterone, and serum-converting enzyme activity were measured in 13 normotensive pregnant women in three sequential periods: 19-21, 29-31, and 38-40 weeks of gestation. The converting enzyme activity was also measured in a group of 6 women with hypertensive pregnancy and an age-matched control group of 35 normal nonpregnant women. Plasma renin activity and plasma aldosterone values were both significantly elevated in the three periods of pregnancy, but plasma aldosterone levels were relatively lower during the first two periods. This is suggested to be secondary to depressed aldosterone secretion by intravascular volume expansion. The serum-converting enzyme activity did not change during pregnancy, and the mean values (1.02 +/- 0.27 U) were lower than those found in the control group (1.23 +/- 0.26 U). Similar low values were found in the hypertensive pregnancy group (1.11 +/- 0.35 U). Therefore, we assume that the converting enzyme is not a limiting factor in the conversion of angiotensin nor does it contribute significantly to the pathogenesis of hypertensive pregnancy.

Spontaneous rupture of the kidney in a patient with acute autoimmune disease.

A percutaneous renal biopsy was performed on a 50-year-old female with rapidly progressive renal failure. The histologic specimen was characteristic of an immune complex disease, most likely systemic lupus erythematosus. Serologic tests were negative. 8 days after the biopsy, there was a spontaneous rupture of the kidney which necessitated nephrectomy. As no connection was found between the biopsy site and the rupture, it was concluded that the rupture was spontaneous in a patient with an immune complex disease.

[Parvovirus B19 myocarditis in a young man with previous non-bacterial meningitis]. / Parvovirus B19-Myokarditis eines jungen Erwachsenen nach abakterieller Meningitis.

HISTORY AND CLINICAL FINDINGS: A 22-year old man presented with fatigue, dyspnea NYHA III and presyncopes that had persisted since a non-bacterial meningitis 3 months before. INVESTIGATIONS: Transthoracic echocardiography revealed a dilated left ventricle with an ejection fraction (EF) reduced to 35-40 % due to global hypokinesia. No pericardial effusion was seen; ECG and lung function test were normal. Serological, immunological and microbiological tests as well as nested PCR analysis of blood leucocytes for detection of cardiotropic pathogens were inconclusive. In endomyocardial biopsies retrieved from the left ventricular posterolateral wall, a chronic macro-phage-rich myocarditis was shown by histopathology and, in addition, Parvovirus B19 was identified as specific pathogen by use of nested PCR analysis. TREATMENT AND COURSE: At physical rest and with ACE inhibitor therapy (2.5 mg ramipril/day), heart failure decreased steadily. Follow-up echocardiography 1 month later revealed a left ventricle that was only slightly dilated with an EF of 50 %. 3 months later, the patient was markedly more load-bearing; the EF amounted to 55-60 %. CONCLUSIONS: Parvovirus B19 should be regarded as potential pathogen in case of suspected myocarditis in adulthood. Whether the previous non-bacterial meningitis was also attributable to this specific pathogen, remains open. Of note, however, the present case report by demonstrating a localized myocardial Parvovirus B19 infection without detectable systemic infection underscores the importance of molecular tests for diagnostic accuracy in manifest organ failure.