Prevalence of diarrhea and enteropathogens in racing sled dogs

BACKGROUND

Diarrhea is highly prevalent in racing sled dogs, although the underlying causes are poorly understood.

HYPOTHESIS

Clostridium perfringens enterotoxin (CPE) and Clostridium difficile Toxin A and B are associated with diarrhea in racing sled dogs.

ANIMALS

One hundred and thirty-five sled dogs.

METHODS

Freshly voided feces were obtained from 55 dogs before racing and from 80 dogs after 400 miles of racing. Samples were visually scored for diarrhea, mucus, blood, and melena. CPE and C. difficile Toxin A and B were detected by ELISA. Samples were cultured for C. perfringens, C. difficile, Campylobacter, Salmonella, and Escherichia coli O157; Giardia and Cryptosporidium spp. were detected via immunofluorescence.

RESULTS

Diarrhea occurred in 36% of dogs during racing, and hematochezia, fecal mucus or melena, or all 3 occurred in 57.5% of dogs. Salmonella was isolated from 78.2% of dogs before racing, and from 71.3% of dogs during racing. C. perfringens and C. difficile were isolated from 100 and 58.2% of dogs before racing, and from 95 and 36.3% of dogs during racing. Dogs were more likely to test positive for CPE during than before racing (18.8 versus 5.5%, P = .021); however, no enteropathogens or their respective toxins were significantly associated with hematochezia or diarrhea.

CONCLUSIONS AND CLINICAL IMPORTANCE

Sled dogs participating in long distance racing have a high prevalence of diarrhea and hematochezia that is not associated with common enteropathogens. It is possible that diarrhea and hematochezia represent the effect of prolonged exercise on the gastrointestinal tract.

[Mixed connective tissue disease and HELLP syndrome in pregnancy]

HISTORY AND ADMISSION FINDINGS

A 35-year-old woman (gravida 4, para 3) was known to have mixed connective tissue disease (MCTD-Sharp's syndrome) for five years, treated with immunosuppressives. She was in the 20 + 4 week of an unwanted pregnancy.

DIAGNOSIS

On admission she had marked eclampsia with severe hypertension (180/130 mmHg), laboratory tests revealing hemolysis, elevated liver enzymes and thrombocytopenia, indicating an HELPP syndrome (severe eclampsia with hemolysis, elevated liver function and low platelets).

TREATMENT AND COURSE

The symptoms worsened over a few days, the patient initially having refused treatment. The fetus died in utero. After drug-induction of labor the fetus was ejected and with further supportive treatment the patient's condition rapidly improved.

CONCLUSION

This patient developed HELPP syndrome in association with MCTD. There is no proof that the collagen disease had a causal or aggravating effect on the development of HELPP syndrome.

[Renovascular hypertension--diagnosis and therapy]

Atherosclerotic renal artery stenosis accounts for most cases of renovascular hypertension (RVH). Hypertensive patients with clinical features suggesting RVH should be submitted to further noninvasive evaluation including duplex Doppler ultrasonography, CT- or MR angiography. Invasive evaluation by contrast-enhanced angiography confirms the diagnosis of renal artery stenosis. However, neither diagnostic test reliably predicts the course of hypertension after revascularisation. The therapeutic approach in hypertensive patients with hemodynamically important renal artery stenosis includes medical or invasive therapy (renal percutaneous transluminal angioplasty, PTRA; renal arterial stent placement, PTRAS; surgical revascularisation). Randomized trials comparing invasive and conservative approaches demonstrated no differences in blood pressure control or renal function. Only patients with clear clinical indications should be submitted to interventional procedures as PTRA, PTRAS and surgical vascular intervention.

Group B Streptococcus (Streptococcus agalactiae) peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD)

Streptococcus agalactiae typically induces serious infections in pregnant women and newborns. Nonpregnant adult patients can also be infected and mortality rate exceeds 40%. CAPD peritonitis is very rarely induced by S. agalactiae. Seven cases have been described previously and all had a very severe course, which included bacteremia, septic shock and death. A 27-year-old male with end-stage renal disease due to membranoprolipherative glomerulonephritis type I, who was on CAPD for 17 months, was admitted with the clinical and laboratory picture of CAPD peritonitis. Severe abdominal pain, shaking chills and fever 38.5 microC were also observed at presentation. Streptococcus agalactiae was isolated from the peritoneal fluid and blood culture was sterile. Under treatment with ceftazidime and tobramycin (i.p.) and vancomycin (i.v.) cultures became negative after 48 hours, abdominal symptoms resolved after 12 days and WBC count in the dialysate normalized after 14 days. As a possible source of infection the patient's partner was shown to be a vaginal carrier of a clone of S. agalactiae identical to that isolated in the peritoneal fluid. S. agalactiae is a rare cause of CAPD peritonitis with potentially very serious consequences. Anal or genital tract colonization is, in general, the source of contamination with S. agalactiae. The microbiological findings in the case presented here suggest that colonization of the patient or of his close environment may be important in the pathogenesis of S. agalactiae-induced CAPD peritonitis.

Color-coded duplex sonography study of arteriovenous fistulae and pseudoaneurysms complicating percutaneous renal allograft biopsy

BACKGROUND

The exact incidence and clinical impact of arteriovenous fistulae (AVF) and pseudoaneurysms as complications emerging from renal allograft biopsy are not well established. We therefore conducted a prospective study using color-coded duplex sonography (CCDS) to determine the frequency, clinical presentation and spontaneous occlusion rate of biopsy-related AVF and pseudoaneurysms in kidney transplant recipients.

METHODS

We investigated 72 consecutive patients undergoing renal allograft biopsy using an automated biopsy technique. CCDS was performed before, immediately after and up to more than 6 months after biopsy. The diagnosis of AVF was based on the presence of perivascular vibration artifacts and detection of typical Doppler curves. Pseudoaneurysms were diagnosed based on the presence of"to-and-fro" signals.

RESULTS

In 5 patients (6.9%), an AVF was detectable before biopsy. Post-biopsy AVF were found in 12 additional patients (16.7%) with a spontaneous occlusion rate of 50% within 48 hours and 75% after 4 weeks. Three (25%) AVF persisted longer than 1 year. Four patients (5.6%) were found to have pseudoaneurysms. All pseudoaneurysms were located closely to AVF and closed spontaneously. None of the post-biopsy AVF and pseudoaneurysms required specific therapy. In 2 patients (2.8%), allograft biopsy lead to significant hemorrhage independent of AVF or pseudoaneurysms.

CONCLUSION

These results indicate that post-biopsy AVF and pseudoaneurysms are a frequent finding after automated renal allograft biopsy. The natural history of these lesions shows a high rate of early occlusion. The present data fail to demonstrate significant clinical impact of AVF and pseudoaneurysms after renal allograft biopsy.

32-year old patient presenting with autoimmune polyglandular syndrome

A 32-year-old student reported fatigue and malaise since two months in the absence of specific symptoms. Clinical examination and extensive laboratory testing revealed no abnormalities at his first presentation. Some weeks thereafter, on re-admission, hyperpigmentation suggestive of Addison's disease was observed and pathognomonic autoantibodies directed against the thyroid gland and the adrenal cortex were detected. Further evaluation led to the diagnosis autoimmune polyglandular deficiency syndrome, also named "Schmidt syndrome", comprising adrenocortical insufficiency (Addison's disease) and lymphocytic thyroiditis (Hashimoto thyroiditis). The diagnosis of polyglandular insufficiency is often delayed due to non-specific symptoms at early disease stages and progression may be rapid, culminating in Addisonian crisis under physical stress or infection, requiring immediate high-dose hormone replacement therapy. Hence, careful re-examination is mandatory to ensure adequate treatment before life-threatening complications occur. Nowadays this type of disease is classified as autoimmune polyglandular syndrome type II (APS type II) with an increased risk of developing insulin-dependent diabetes mellitus (IDDM), vitiligo, alopecia, pernicious anaemia, coeliac disease, myasthenia gravis and primary hypogonadism. The cause of the disease remains obscure but in addition to an autosomal dominant trait with variable penetrance some hints at viral infection triggering the disease process exist.

Is narcolepsy a REM sleep disorder? Analysis of sleep abnormalities in narcoleptic Dobermans

Narcolepsy is a chronic sleep disorder marked by excessive daytime sleepiness, cataplexy, sleep paralysis, and hypnagogic hallucinations. Since the discovery of sleep onset REM periods (SOREMPs) in narcoleptic patients, narcolepsy has often been regarded as a disorder of REM sleep generation: REM sleep intrudes in active wake or at sleep onset, resulting in cataplexy, sleep paralysis, or hypnagogic hallucinations. However, this hypothesis has not been experimentally verified. In the current study, we characterized the sleep abnormalities of genetically narcoleptic-cataplectic Dobermans, a naturally occurring animal model of narcolepsy, in order to verify this concept. Multiple sleep latency tests during the daytime revealed that narcoleptic Dobermans exhibit a shorter sleep latency and a higher frequency of SOREMPs, compared to control Dobermans. The total amount of time spent in wake and sleep during the daytime is not altered in narcoleptic dogs, but their wake and sleep patterns are fragmented, and state transitions into and from wake and other sleep stages are altered. A clear 30 min REM sleep cyclicity exists in both narcoleptic and control dogs, suggesting that generation of the ultradian rhythm of REM sleep is not altered in narcoleptics. In contrast, cataplexy displays no cyclicity and can be elicited in narcoleptic animals anytime with emotional stimulation and displays no cyclicity. Stimulation of a cholinoceptive site in the basal forebrain induces a long-lasting attack of cataplexy in narcoleptic dogs; however, bursts of rapid eye movements during this state still occur with a 30 min cyclicity. Sites and mechanisms for triggering cataplexy may therefore be different from those for REM sleep. Cataplexy and a dysfunction in the maintenance of vigilance states, but not abnormal REM sleep generation, may therefore be central to narcolepsy.

Sulpiride, a D2/D3 blocker, reduces cataplexy but not REM sleep in canine narcolepsy

Cataplexy, an abnormal manifestation of REM sleep atonia, is currently treated with antidepressants. These medications also reduce physiological REM sleep and induce nocturnal sleep disturbances. Because a recent work on canine narcolepsy suggests that the mechanisms for triggering cataplexy are different from those for REM sleep, we hypothesized that compounds which act specifically on cataplexy, but not on REM sleep, could be developed. Canine studies also suggest that the dopamine D2/D3 receptor mechanism is specifically involved in the regulation of cataplexy, but little evidence suggests that this mechanism is important for REM sleep regulation. We therefore assessed the effects of sulpiride, a commonly used D2/D3 antagonist, on cataplexy and sleep in narcoleptic canines to explore the possible clinical application of D2/D3 antagonists for the treatment of human narcolepsy. Both acute and chronic oral administration of sulpiride (300 mg/dog, 600 mg/dog) significantly reduced cataplexy without noticeable side effects. Interestingly, the anticataplectic dose of sulpiride did not significantly reduce the amount of REM sleep. Sulpiride (and other D2/D3 antagonists) may therefore be an attractive new therapeutic indication in human narcolepsy.

Renal oncocytoma of the native kidney after renal transplantation

Patients with acquired cystic kidney disease (ACKD) are at an increased risk of renal neoplasms. Frequent tumors are adenomas and renal cell carcinomas. However, renal oncocytomas may occur in patients with ACKD. Little is known about oncocytomas of the native kidney following renal transplantation. By means of B scan ultrasonography, a solid and echo-inhomogeneous renal mass was incidentically observed in the right native kidney of a 28-year-old female patient with ACKD 4 years following renal transplantation. A nephrectomy was performed. The histological examination revealed a renal oncocytoma. The increased prevalence of neoplasms in the case of ACKD and following renal transplantation requires careful monitoring of the patients concerned. In very rare cases a renal oncocytoma may develop in the native kidney after renal transplantation.

[Immobilization hypercalcemia as a complication of polyneuropathy]

Prolonged immobilization or physical inactivity has been shown to produce increased bone resorption due to enhanced osteoclastic activity and diminished bone formation. These skeletal changes are a typical complication in tetraplegic patients, who are at risk of developing hypocalcemia. Hypercalciuria is the most characteristic symptom. However, some patients develop hypercalcemia, which is infrequent in these patients, and the hypercalcemia can become a life-threatening complication. Until now, it has been unclear why a small percentage of immobilized patients develop hypercalcemia. Here we present a case of symptomatic hypercalcemia (serum calcium: 3.5 mM/l) following immobilization due to a critical illness polyneuropathy. The diagnosis could be established after malignant hypercalcemia, primary hyperparathyroidism, and other causes of hypercalcemia were excluded. Treatment with intravenous saline, furosemide, and calcitonin was not effective in lowering serum calcium. Treatment with pamidronate (Aredia) was successful and reduced the serum calcium to normal values.

Chronic oral administration of CG-3703, a thyrotropin releasing hormone analog, increases wake and decreases cataplexy in canine narcolepsy

The effects on cataplexy and daytime sleep of acute and chronic oral administration of CG-3703, a potent TRH analog were assessed in canine narcolepsy. CG-3703 was found to be orally active and to reduce cataplexy (0.25 to 16 mg/kg) and sleep (8 and 16 mg/kg) in a dose-dependent manner. Two-week oral administration of CG-3703 (16 mg/kg) significantly reduced cataplexy and daytime sleep. The anticataplectic effects of CG-3703 were not associated with changes in general behavior, heart rate, blood pressure, rectal temperature, blood chemistry and thyroid function. Although drug tolerance for the effects on cataplexy and sleep were observed during the second week of chronic drug administration, therapeutic efficacy on cataplexy was improved with individual dose adjustment (final dose range: 16 to 28 mg/kg, p.o.). These results suggest that TRH analogs could be a promising new form of treatment for human narcolepsy.

Inheritance of von Willebrand's disease in a colony of Doberman Pinschers

OBJECTIVE

To determine the mode of inheritance of von Willebrand's disease (vWD) and perform linkage analysis between vWD and coat color or narcolepsy in a colony of Doberman Pinschers.

ANIMALS

159 Doberman Pinschers.

PROCEDURE

von Willebrand factor antigen (vWF:Ag) concentration was measured by use of ELISA, and results were used to classify dogs as having low (< 20%), intermediate (20 to 65%), or high (> 65%) vWF:Ag concentration, compared with results of analysis of standard pooled plasma. Buccal bleeding time was measured, and mode of inheritance of vWD was assessed by pedigree analysis.

RESULTS

von Willebrand's disease was transmitted as a single autosomal gene defect. Results suggested that 27.04% of dogs were homozygous for vWD, 62.26% were heterozygous, and 10.69% did not have the defect. Most homozygous and some heterozygous dogs had prolonged bleeding times. Dogs with diluted coat colors (blue and fawn) were significantly overrepresented in the homozygous group, compared with black and red dogs, but a significant link between vWD and coat color was not detected.

CONCLUSIONS AND CLINICAL RELEVANCE

von Willebrand's disease is transmitted as an autosomal dominant trait with variable penetrance; most dogs in this colony (89.3%) were carriers of vWD. Homozygosity for vWD is not likely to be lethal. Some heterozygous dogs have prolonged bleeding times. An association between diluted coat colors and vWD may exist.

Dopamine D3 agonists into the substantia nigra aggravate cataplexy but do not modify sleep

We have recently demonstrated that local perfusion of dopaminergic D2/D3 agonists into the ventral tegmental area (VTA) significantly aggravates cataplexy and increases sleep in narcoleptic Dobermans. We further assessed the roles of the mesostriatal dopaminergic system and found that local perfusion of quinpirole and 7-OH-DPAT into the substantia nigra (SN) significantly aggravated cataplexy, while perfusion of a D2/D3 antagonist significantly reduced cataplexy. Neither a D1 agonist nor a D1 antagonist modified cataplexy. SN perfusion of quinpirole did not significantly modify sleep, while VTA perfusion significantly increased the drowsy state. Although autoregulation of the VTA and SN dopaminergic neurons are involved in the regulation of cataplexy, both structures have distinct roles for the regulation of sleep.

Dopamine D3 agonists into the substantia nigra aggravate cataplexy but do not modify sleep [corrected]

We have recently demonstrated that local perfusion of dopaminergic D2/D3 agonists into the ventral tegmental area (VTA) significantly aggravates cataplexy and increases sleep in narcoleptic Dobermans. We further assessed the roles of the mesostriatal dopaminergic system and found that local perfusion of quinpirole and 7-OH-DPAT into the substantia nigra (SN) significantly aggravated cataplexy, while perfusion of a D2/D3 antagonist significantly reduced cataplexy. Neither a D1 agonist nor a D1 antagonist modified cataplexy. SN perfusion of quinpirole did not significantly modify sleep, while VTA perfusion significantly increased the drowsy state. Although autoregulation of the VTA and SN dopaminergic neurons are involved in the regulation of cataplexy, both structures have distinct roles for the regulation of sleep.

Dialysis and pregnancy--a case report and review of the literature

We report on a patient with an eight-year history on maintenance hemodialysis treatment without residual renal function in whom pregnancy was successfully managed through to the 29th week. During this time, under carefully modified dialysis treatment, the nephrologic course, as well as materno-fetal flow relationships were unremarkable. Fetal development was appropriate for gestational age. However, pregnancy was complicated by polyhydramnios, which necessitated i.v. tocolysis. In the 28 + 6th week of gestation, cesarean section was performed because of an antibiotic-resistant fever of unclear origin which ceased within two days of delivery. Although the postnatal course of the adequately developed baby was complicated by the respiratory distress syndrome, normal development continued. We emphasize that the intensive interdisciplinary cooperation of nephrologists and obstetricians is imperative for the successful management of pregnancy under these conditions. In these pregnancies, the main fetal problems consist of premature labor because of polyhydramnios, preterm delivery, intrauterine growth retardation and stillbirth. The mother is threatened by the development of superimposed pre-eclampsia, left ventricular failure because of volume overload and progressive anemia. In order to maintain a well-balanced homeostasis, intensification of dialysis therapy by an increase in frequency and duration is the most important therapeutic approach. Accurate fetal monitoring including frequent examination of the feto-maternal circulation by Doppler sonography as well as attentive surveillance of the mother is required to recognize the above mentioned complications.

Successful treatment of pulmonary Mycobacterium xenopi infection in a natural killer cell-deficient patient with clarithromycin, rifabutin, and sparfloxacin

Isolation of Mycobacterium xenopi from the respiratory tract may indicate pneumonia, often clinically indistinguishable from tuberculosis. Resistance to the classic antituberculous drugs renders the treatment of these infections problematic. We report on a case of cavernous pneumonia caused by M. xenopi in a 36-year-old male with natural killer cell deficiency but without severe immunodeficiency. He was successfully treated with a novel triple-drug combination comprising clarithromycin, sparfloxacin, and rifabutin. An impressive subsequent regression of pathological pulmonary changes was observed, and mycobacteria could no longer be detected. The therapeutic potential of clarithromycin and sparfloxacin in the treatment of M. xenopi infections is discussed.

Neuronal activity in the cholinoceptive basal forebrain of freely moving narcoleptic dobermans

Cholinergic stimulation in the basal forebrain (BF) triggers cataplexy in canine narcolepsy. Extracellular single unit recordings in the BF were carried out in freely moving narcoleptic dogs to study the neuronal mechanisms mediating cataplexy induction in the BF. Among the 64 recorded neurons, 12 were wake-active, three were slow wave sleep (SWS)-active, 17 were wake-/REM-active, 11 were REM sleep-active, three were cataplexy-active, and the other 18 were state-independent. Systemic administration of physostigmine, a cholinesterase inhibitor, induces status cataplecticus, decreases SWS and increases acetylcholine levels in the BF. Firing of most of the state-dependent neurons in the BF was significantly modified by physostigmine. Some of these neurons may thus mediate sleep stage changes or the effect on cataplexy observed after cholinergic stimulation in the BF.

Hepatic portal venous gas following emergency endoscopic sclerotherapy of gastric varices

Hepatic portal venous gas (HPVG) is a rare condition, usually associated with extended bowel necrosis or intra-abdominal infection. Herein, we report a case of HPVG following endoscopic sclerotherapy for bleeding gastric varices. A 50-year-old female with a history of alcoholic liver disease was referred to our hospital because of hematemesis. Emergency endoscopic sclerotherapy was performed to control bleeding gastric varices. Twelve hours later, HPVG was demonstrated by ultrasound and confirmed by duplex sonography, which spontaneously resolved 2 hours later. The patient remained well throughout this time, and was released with no major sequelae. This case supports the view that HPVG can also present as a benign finding, in particular, following diagnostic and therapeutic procedures of the gut. The underlying cause determines the clinical significance and prognosis of HPVG.

Development of cataplexy in genetically narcoleptic Dobermans

Forty-two genetically narcoleptic Doberman puppies [20 pure narcoleptic (N) puppies (from four narcoleptic x narcoleptic crosses) and 22 backcross narcoleptic (BN) puppies (from six narcoleptic x heterozygous crosses)] were systematically observed during the developmental period (4-24 weeks) to assess the age at onset and severity of cataplexy, a pathological manifestation of REM sleep atonia seen in narcolepsy. The mean age of onset of cataplexy was 9.69 +/- 1.15 weeks, with a median age of 7 weeks. The severity of cataplexy increased with age and reached a plateau at around 16-24 weeks. The effects of cross type (N vs BN) and sex on the development of cataplexy were analyzed. There was no difference in severity between N and BN puppies (P = 0.51). However, females had more severe cataplexy than males (P = 0.01), and this trend was preserved in five of the six litters that had both male and female puppies. These results suggest that the pathophysiological process in genetic canine narcolepsy emerges during the early developmental period and that it may involve a differential development in males and females. Furthermore, our results revealed that cataplexy onset corresponds to the emergence of adult-like REM sleep and to previously reported neuroanatomical and neurochemical abnormalities in canine narcolepsy.

Central administration of vitamin B12 aggravates cataplexy in canine narcolepsy

Experimental evidence in canine narcolepsy suggests that central cholinergic systems are critically involved in the regulation of cataplexy, an abnormal manifestation of REM sleep atonia. In the current study, we found that intracerebroventricular perfusion of methyl-B12, (10(-5)-10(-2) M), significantly aggravated cataplexy and enhanced REM sleep in narcoleptic dogs. Choline, a direct precursor of acetylcholine, was also found to aggravate cataplexy, while cyano-B12, a vitamin B12 analog without methyl donating abilities, had no effect on cataplexy. Since both methyl-B12 and choline are reported to enhance acetylcholine synthesis, enhancement of the biosynthesis of acetylcholine may be involved in the effects observed in canine narcolepsy. Our results suggest that central administration of methyl-B12 has the potential to modulate both normal and pathological REM sleep.

[Spontaneous portasystemic shunt in liver cirrhosis: imaging with color-coded duplex ultrasonography]

PURPOSE

To demonstrate the usefulness of B-scan ultrasonography and color Doppler ultrasonography (CCDS) in the diagnosis of lumbal and splenorenal collateral veins in patients with liver cirrhosis.

METHOD

46 patients with histologically proven liver cirrhosis were examined by means of B-scan ultrasonography. CCDS was used to demonstrate the vascular character of mass-like lesions or tortuous tubular structures. Esophageal varices were demonstrated in 23 (50%) and ascites in 6 patients (13%).

RESULTS

In 5 out of 46 patients (10.9%) we demonstrated lumbal and splenorenal portosystemic venous collaterals by B-scan- and CCDS. In 2 patients localized venous collaterals were demonstrated. No ascites was found in patients with accessory portosystemic shunts. CCDS showed the patency of these spontaneous portosystemic shunts.

CONCLUSION

In patients with chronic liver disease CCDS is a noninvasive method to demonstrate spontaneous portosystemic shunts due to portal hypertension. The method provides information concerning patency and flow direction of the collateral veins.

Renal artery stenosis: evaluation with colour duplex ultrasonography

BACKGROUND

Detection of renal artery stenoses (RAS) by means of duplex Doppler ultrasound with direct scanning of the main renal arteries is subject to numerous limitations. Using semiquantitative analysis of the Doppler curve, which can be recorded from intrarenal arteries, it is possible to detect RAS unaffected by the problems of direct Doppler scanning of the renal arteries.

METHODS

Both angiography of the renal arteries and colour duplex ultrasonography (US) of the intrarenal vessels (interlobar arteries) were performed in 214 patients (53.2 +/- 14.1 years) with severe arterial hypertension. Angiography was used as 'gold standard' in the diagnosis of RAS and the Doppler results were compared with the subsequent findings on angiography. At angiography, the reduction of diameter > 70% was assessed as haemodynamically effective RAS. For the duplex Doppler diagnosis of RAS the following parameters were calculated: (a) resistive index (RI) of each kidney, and (b) side-to-side differences of the resistive indices (delta RI) between the right and left kidney.

RESULTS

Angiography demonstrated 59 RAS (> 70%) in 53 patients, including six with bilateral RAS. By means of duplex US we found a significant difference of RI between kidneys with RAS (0.48 +/- 0.11) and without RAS (0.63 +/- 0.08; P < 0.001). In addition, a significant difference of the delta RI was noted in patients with RAS (24.4% +/- 12.5%) and the controls without RAS (3.6% +/- 2.7%). Using a combination of both RI and delta RI, threshold values of RI = 0.45 resp. delta RI = 8% yields a sensitivity of 92.5% and a specificity of 95.7% in the detection of haemodynamically effective RAS.

CONCLUSIONS

Colour duplex US with calculation of the RI and delta RI of intrarenal arteries is a valuable non-invasive test assessing the haemodynamic effects of a RAS. Low costs and safety support the use of the Doppler technique in screening for renovascular disease.

The use of duplex sonography in the diagnosis of renal artery stenosis

Both direct and indirect duplex sonography (DS) permit the diagnosis of significant renal artery stenosis. The validity of direct DS, based on the detection of increases in the blood velocity in stenotic arteries, is affected by numerous factors (inappropriate examination conditions, presence of vascular variants). In the technique of indirect DS, renal artery stenosis is detected via changes in the hemodynamics of intrarenal vessels ('tardus-et-parvus' phenomenon). Various evaluation parameters (signal shape, acceleration time, acceleration index, resistance index, pulsatility index) have proven useful for signal analysis. The intraindividual comparison of the two sides is an important instrument of stenosis detection in indirect DS. In clinically selected populations of hypertensive patients, DS may be used as a method of stenosis screening. DS has proven its practical value as a follow-up method after angioplastic intervention. It remains to be shown in future investigations whether "functional' classification of the degree of stenosis on the basis of Doppler sonographic findings is feasible.

[Acute pulmonary syndrome and cavernous pulmonary tuberculosis in a patient with sickle cell disease]

HISTORY AND CLINICAL FINDINGS

A 17-year-old girl from Zaire was admitted to hospital with fever, cough, dyspnoea and severe chest pain. In addition to marked anaemia (haemoglobin 6.6 g/dl) she was known to have cavitary/exudative pulmonary tuberculosis (PTb) with bilateral basal infiltrations.

INVESTIGATIONS

Blood gas analysis indicated partial respiratory failure (pO2 55 mm Hg, pCO2 36 mm Hg). Blood smear under air exclusion showed erythrocyte sickling. Haemoglobin electrophoresis demonstrated 92.7% HbS and thus confirmed sickle cell anaemia. A small spleen on sonography and the presence of Howell-Jolly bodies were interpreted as signs of functional asplenia. Microbiological and radiological tests confirmed exudative-cavitary PTb.

TREATMENT AND COURSE

The findings were interpreted as due to an acute chest syndrome, caused by sickle cell thrombi in the pulmonary blood vessels, precipitated by the PTb. Transfusion of two units of erythrocyte concentrates led to improvement of the chest pain and the respiratory failure within a few hours. The PTb was successfully treated without any complications.

CONCLUSION

Acute chest syndrome is a vascular occlusive complication of sickle cell disease, pulmonary tuberculosis precipitating the development of this acute condition. Administration of erythrocyte concentrate rapidly improves the signs and symptoms.

[Femoral hernia: diagnosis with B-image, duplex and color-coded Doppler ultrasound]

The diagnosis of femoral hernias depends on the recognition of their clinical features. In many cases femoral hernias were incorrectly diagnosed. B-Scan ultrasonography, duplex- and colour-coded Doppler sonography were used to diagnose a femoral hernia in a 60-year old female patient who developed a groin lump after femoral artery puncture. The diagnostic procedure could easily differentiate between haematoma, pseudo-aneurysm, arteriovenous fistula and femoral hernia by the characteristic Doppler spectrum and colour coding. B-Scan ultrasonography, duplex- and colour-coded Doppler sonography can accurately detect femoral hernias and should be routinely used in patients with any kind of groin lump.

[Prevalence of goiter in the Aachen area. Ultrasound volumetry of the thyroid gland of 1,336 adults in an endemic goiter region]

AIM

The aim of the study was to assess the prevalence of thyroid enlargement by ultrasonic volume measurements.

RESULTS

1336 adults living in the iodine-deficient area of Aachen, West Germany (760 females, 576 males, mean age: 54.05 +/- 16.09 years) were included in the investigation. The ultrasonic examination was carried out in patients who did not suffer from thyroid disease at the time of study.

RESULTS

The thyroid volume was age-dependent and varied from 13.3 +/- 10.4 ml in patients < 21 years to 29.9 +/- 24.3 ml in patients > 70 years. The prevalence of thyroid enlargement ranged from 14.3% in young people to 51.3% in the elderly. There was no difference in the volumes of the left and right thyroid lobe. The prevalence of thyroid enlargement was higher in females compared to males (p < 0.05). Retrosternal thyroid mass was detected in 25% of all patients > 70 years.

CONCLUSION

There is evidence of a high prevalence of thyroid enlargement in iodine-deficient areas.

Medullary nephrocalcinosis: sonographic findings in adult patients

Medullary nephrocalcinosis occurs in various diseases as a non-specific renal manifestation. We present 5 patients (hypophosphataemic rickets, type 1 renal tubular acidosis, primary hyperparathyroidism, hypercalcaemia of unclear origin, chronic renal insufficiency requiring dialysis) in whom a medullary nephrocalcinosis was demonstrated by means of sonographically detectable changes in the renal medulla region. The sonographic appearance of medullary nephrocalcinosis is characterized by detection of echo-enhanced structures in the region of the renal pyramids. The presence of a medullary nephrocalcinosis can generally be confirmed with adequate reliability on the basis of sonographic findings and characteristic clinical pictures. In individual cases it is difficult to distinguish between medullary nephrocalcinosis and renal calyx calculi.

Which bicarbonate concentration is adequate to lactate-buffered substitution fluids in maintenance hemofiltration?

We investigated the metabolic and hemodynamic effects of a lactate- and a bicarbonate-buffered (bicarbonate concentration 31.4 mmol/l, type I) hemofiltration substitution fluid in a prospective crossover study of 3 weeks each in 11 patients on maintenance hemofiltration. The lactate-buffered hemofiltration (lactate concentration 34-44.5 mmol/l) lead to hyperlactatemia in all patients without signs of overt lactic acidosis but showed a better control of acid-base balance (pH, base excess, standard bicarbonate) than the type I bicarbonate-buffered fluid (p < 0.01). In 6 patients a higher concentration of bicarbonate- (39.7 mmol/l, type II) buffered fluid was tested. The parameters of acid-base balance showed a better control during type II than during type I bicarbonate hemofiltration and were similar to the lactate-buffered phase. Plasma lactate levels between type I and type II bicarbonate hemofiltration were not different. Also in the steady state phase of the treatment (days 7-9 [week 3]) parameters of acid-base balance rose more to normal values during type II than during lactate-buffered hemofiltration. Hemodynamic parameters showed no differences between the three types of buffers used. Furthermore, also the type II bicarbonate fluid was well tolerated. Bicarbonate in a higher concentration (39.7 mmol/l) proved to be a safe and practical alternative to lactate-buffered hemofiltration.

Diagnostic value of indirect pancreatic function test in serum of anuric patients with chronic renal failure

Although patients with chronic renal failure have a high incidence of chronic pancreatic disease, the condition is frequently overlooked. We have modified the pancreolauryl test--an indirect pancreatic function test--for anuric patients. The test permitted good discrimination between patients with chronic pancreatic disease and those with a normal pancreas when serum levels of fluorescein were measured 10 h after administration with a standard meal. The sensitivity at this time interval was 80% and the specificity 83%. We conclude that the pancreolauryl test with serum measurements provides a simple, noninvasive, and reliable diagnostic test for chronic pancreatic disease in anuric patients with chronic renal failure.

[Arteriovenous fistula and kidney pelvis thrombus after percutaneous kidney puncture]

Percutaneous renal biopsy was performed in a 40-year old transplant recipient suffering from renal function impairment. The examination of the main transplant artery by duplex Doppler ultrasonography showed normal values for the resistive index and renal blood flow volume. Postbioptic realtime ultrasonography showed an echogenic mass in the renal collecting system, which was dilatated in prior examinations. In addition, we found an arteriovenous fistula by colour coded Doppler ultrasonography showing a characteristic Doppler wave-form shape in an interlobar artery. No changes in the resistive index and renal flow volume could be demonstrated by Doppler examination of the main renal artery. The complications of percutaneous biopsy disappeared spontaneously. Although the incidence of major complications after renal graft biopsy with the automated biopsy instrument is very low, our report demonstrates typical complications following percutaneous renal biopsy. We conclude that B-scan and colour coded Doppler ultrasonography are sensitive diagnostic methods to observe patients post biopsy for potential complications.

Response of vasoactive substances to reduction of blood volume during hemodialysis in hypotensive patients

Hypotension is a frequent complication in patients subjected to regular hemodialysis. Insufficient regulation of blood pressure following dialysis with ultrafiltration has been attributed to a lack in hormone activation. To determine whether altered production of vasoactive hormones is involved in the breakdown of blood pressure regulation during hemodialysis (HD), blood volume (BV), atrial natriuretic peptide (ANP), plasma renin activity (PRA), aldosterone (Aldo), norepinephrine (NE), epinephrine (Epi), intact immunoreactive parathyroid hormone (iPTH) and arginine vasopressin (AVP) were examined. The relative BV was measured by continuous hemoglobinometry during the HD period of about 240 min. The total decrease in BV at the end of treatment was 23.5 +/- 4.8% of the pretreatment value. Systolic blood pressure (SBP) was 99.6 +/- 23.0 mmHg before dialysis compared with 74.6 +/- 18.8 mmHg at the end of dialysis and heart rate (HR) increased from 76.3 +/- 5.5/min before to 92.0 +/- 10.0/min at the end of dialysis. Despite the wide range of interindividual variance, the hormonal changes indicate that hypotensive patients under HD develop reduced sensitivity of the angiotensin-renin, adrenergic and AVP systems to volumetric stimuli. A paradoxical activation in iPTH and PRA independent Aldo secretions is apparent.

Response of vasoactive substances to intermittent ultrafiltration in normotensive hemodialysis patients

The changes in blood volume (BV), atrial natriuretic peptide (ANP), plasma renin activity (PRA), aldosterone (Aldo), norepinephrine (NE), epinephrine (Epi), parathyroid hormone (PTH), arginine vasopressin (AVP) and the cyclic nucleotides cAMP and cGMP were measured during a fluctuating BV cycle in 15 patients with end-stage renal failure maintained on chronic hemodialysis (HD). HD consisted of 4 periods of about 60 min each. The first half of each HD period consisted of ultrafiltration (UF) greater than 1,000 ml/h, and the second half consisted of no UF. Changes in relative BV were measured using continuous hemoglobinometry. Total BV at the end of treatment was 74.3 +/- 6.9% of the pretreatment volume. A significant positive correlation between BV and the levels of ANP, PTH, Epi and cGMP and an inverse correlation between BV and PRA, Aldo, AVP and NE were demonstrated. While mean values of NE and AVP levels were directly related to actual changes in BV, individual values did not homogeneously reflect this relationship. The cyclic nucleotides cGMP and cAMP did not follow immediate BV changes, but showed a significant decrease correlated with diminished BV. Based on a pre-postdialysis analysis, significant changes in PRA and Aldo were missing. It seems possible that vascular stability in dialysis patients may be maintained by the response of NE and AVP, and not by the renin-aldosterone system. The changes in ANP and cGMP values correlated most significantly (r = 0.38 and r = 0.51, p < 0.005) with the changes in BV, but no single variable could explain the blood pressure regulation during HD with intermittent rapid UF.

Secondary hyperparathyroidism and sonographic evaluation of parathyroid gland hyperplasia in dialysis patients

Ninety-six hemodialysis patients were examined by ultrasonography of the parathyroid glands to study the prevalence of parathyroid gland hyperplasia and to assess the relevance of sonography in the evaluation of secondary hyperparathyroidism. The results were compared with clinical, biochemical and radiological parameters. Thirty-two (33.3%) patients had sonographically enlarged glands. Of them 19 had 1 and 13 had 2 and more enlarged glands. Patients with enlarged glands, compared to those with undetected glands, had a significantly higher frequency of bone and joint pains (65.5% vs 40.6%), radiological features of hyperparathyroid bone disease (in hands 28.1% vs 6.9%, in acromioclavicular joints 37.5% vs 13.6%) and higher levels of intact serum parathyroid hormone (1-84) concentration (52.8 +/- 47.9 pmol/l vs 18.1 +/- 18.0 pmol/l) and serum alkaline phosphatase concentration (260.2 +/- 201.1 U/l vs 129.8 +/- 127.3 U/l). Those with enlarged glands had been on dialysis for a longer period (87.7 +/- 51.0 months vs 62.5 +/- 47.4 months). The severity of secondary hyperparathyroidism increased with the number of enlarged glands. Our study shows that ultrasonography is a useful noninvasive screening method for the evaluation of secondary hyperparathyroidism in patients on hemodialysis and that sonographically enlarged glands may be a measure of the severity of secondary hyperparathyroidism.

Bedside ultrasound in decision making for emergency surgery: its role in medical intensive care patients

During an 18-month period the authors followed 1,024 patients referred to a general medical intensive care unit. A total of 7% of these patients underwent emergency surgery at some point during their admission. The role of abdominal ultrasound in the decision-making process for these emergency surgical interventions was evaluated and the patients were identified for whom the pathologic result of sonography was regarded sufficient to operate without any additional imaging procedures. Of 71 patients with unexpected surgical emergencies, abdominal ultrasound provided a definite diagnosis for 18 patients (25%), and the decision to operate could be made without delaying for further or more invasive diagnostic techniques. In all cases the sonographic diagnosis was confirmed during the operation. The critical care patients most likely to benefit from bedside ultrasound in a surgical emergency were those with hemorrhage of unknown origin (44%) or septicemia from an undetected focus (39%). The most frequent site of operation where ultrasound was considered diagnostic was the urinary tract (56%), particularly in emergencies following renal transplantation.

[Psychosocial factors of preserving health? Prospective studies of breast cancer, bronchial cancer and fibrocystic mastopathy]

Do psychosocial factors affect the development of health? 156 patients were interviewed and tested before a breast biopsy or before the initial medical treatment of lung cancer. Multiple regressions examined the influence of age, diagnosis (tumor stage) and different psychosocial parameters as dependent variables the development of health after 2 or 5 years as independent variables. The breastbiopsy-group (n = 52) shows five psychological variables being effective in a positive (health promoting) manner: autonomy, emotional outlet, expression of one's needs, family support, lack of life stress. In lung cancer (n = 104) the development of health 2 years after diagnosis is only influenced by the type of tumor (small cell versus non small cell) and by the initial tumor stage. A structuralequation model (LISREL) shows for the first 3 months of illness that almost exclusively biological variables have an influence on psychological variables. Despite this family dynamics had a moderate effect on the patient's general wellbeing (Karnoffsky-Index).

Sonographic changes of the pancreas in chronic renal failure

Several abnormalities regarding pancreatic morphology and function have been reported in patients with chronic renal failure (CRF) with an incidence as high as 72%. In a prospective study we investigated 96 outpatients from our chronic ambulatory hemodialysis program by abdominal ultrasound. Of the patients with CRF, 20.6% were found to have morphologic alterations of the pancreas compared to 4.7% of controls. Although pathologic sonograms of the pancreas correlated with biliary disease, hyperparathyroidism and years of hemodialysis, the most obvious etiologic factor appeared to be the duration of CRF. Possible pathogenetic mechanisms are discussed and screening abdominal ultrasound examinations in patients with long-standing CRF are recommended.