Syndrome of inappropriate anti-diuresis induces volume-dependent hypercalciuria

Hyponatremia is associated with bone demineralization. We hypothesized that, during hyponatremia, calciuria and calcium balance depend on volemic status. We evaluated calciuria in patients with hyponatremia, secondary to SIAD or hypovolemia. Patients with SIAD exhibited a volemic expansion that was associated with hypercalciuria. Calciuria was proportional to markers of volemia.

INTRODUCTION

Chronic mild hyponatremia has been associated with bone demineralization of unknown mechanisms. During chronic hyponatremia, arginine-vasopressin secretion can result from hypovolemia or from syndrome of inappropriate anti-diuresis (SIAD) that leads to a slightly volemic expansion. Since volemia determines renal calcium excretion and balance, we evaluated calcium homeostasis in patients with chronic hyponatremia, related to SIAD or to hypovolemia.

METHODS

We retrospectively included all patients referred to our Department between May 2006 and May 2014 for hyponatremia, resulting from SIAD or chronic hypovolemia. None had edema, cirrhosis, cardiac, or renal insufficiency. Exploration included estimation of volemia, extracellular fluid volume (ECFV) measurement with inulin, and calcium homeostasis.

RESULTS

In total, the SIAD and hypovolemic groups included 22 and 7 patients, respectively. The SIAD group exhibited signs of increased volemia: higher glomerular filtration rate, higher fractional excretion of uric acid, and lower plasma renin. ECFV exceeded that of the hypovolemic group and was above usual values. There was no difference between the two groups regarding plasma calcium, PTH, and vitamin D. However, in the SIAD group, calciuria was higher than in the hypovolemic group, reaching levels of hypercalciuria. Furthermore, there was a positive correlation between calciuria and markers of volemia.

CONCLUSIONS

Our results show that SIAD results in a volemic expansion tendency that is associated with a decrease in renal calcium reabsorption and thus hypercalciuria, whereas in the hypovolemic group, calciuria was not increased. Therefore, renal loss of calcium and bone demineralization in SIAD patients could be partly induced by volemic expansion.

Compression of the peroneal nerve by a neurofibroma originating from collaterals of the peroneal nerve: a case report

BACKGROUND

Paralysis of the external popliteal sciatic nerve is a frequent pathological condition that occurs after trauma. However, etiologies other than trauma, such as tumors, are also possible. The sensory collaterals of the external popliteal sciatic nerve have a small territory of innervation at the knee, and tumors involving these nerves become symptomatic after compression of the motor nerves. We here describe the first reported case of this phenomenon.

CASE PRESENTATION

This case involved a lesion compressing the origin of the external popliteal sciatic nerve of a 13-year-old Moroccan boy diagnosed with a neurofibroma. He developed functional impairment of his left lower limb during a football game, and examination revealed a steppage gait. The initial diagnosis was stretching of the peroneal nerve. The definitive diagnosis of a neurofibroma was revealed by imaging and confirmed by surgery and pathology. Treatment involved total removal of the tumor; however, our patient's steppage gait persisted.

CONCLUSIONS

Our patient developed compression of the external popliteal sciatic nerve from a tumor growing on a collateral nerve. Early diagnosis is an absolute necessity in such cases. Trauma and tumors of sensory nerves can distort the diagnosis, as in this case. Ultrasound and magnetic resonance imaging can contribute to an accurate diagnosis in patients with neuropathy in the absence trauma or tomacula.

Thyroid disorders during interferon alpha therapy in 625 patients with chronic hepatitis C: a prospective cohort study

AIM

to report the prevalence, risk factors, management and long-term outcome of thyroid disorders caused by INFalpha in patients with chronic hepatitis C.

PATIENTS AND METHODS

From January 1991 to December 2004, 625 patients with chronic hepatitis C underwent INFalpha therapy. TSH assay was normal and antithyroperoxidase antibodies (anti-TPO) was performed before onset antiviral treatment; then TSH was performed every 2 months in all patients during therapy, and every 3 months after treatment.

RESULTS

58 patients developed thyroid disorder (8.9%). Mean age was 50.6+/-13 years; sex ratio: 1 M/2 F; the anti-TPO antibodies were positive before onset antiviral treatment in 9 patients (13.8%). 26 patients developed hypothyroidism (44.8%), 9 patients developed hyperthyroidism (15.5%) and among them 3 cases of Grave's disease. Biphasic thyroiditis occurred in 21 patients (36.2%), anti-TPO increase during treatment in 2 patients (3.5%) without hypothyroidism. The dysthyroidism was more frequent in risk in female gender (p<0.05) and in the group with positive antiTPO antibodies before treatment (p<0.02).

CONCLUSION

Female gender and positive antiTPO antibodies are the predictive factors of development of the thyroid dysfunction during INFalpha therapy.

Low rectal volumes in patients suffering from fecal incontinence: what does it mean?

BACKGROUND

Rectal perception and adaptation to distension are widely heterogeneous in subjects with faecal incontinence.

AIM

To quantify rectal physiology in patients with incontinence and low maximum rectal volume, according to AGA guidelines on anorectal testing techniques.

PATIENTS AND METHODS

148 patients (12 men, 136 female) with incontinence to liquid and/or solid stools were investigated. Distending isobaric procedures were carried out using an electronic barostat in order to analyse perception and adaptation of the rectum.

RESULTS

Pain during isovolumic rectal distension at a level of 100 mL or less was experienced in 21 subjects (14.2%). As defined by isobaric distensions, incontinent patients with low MTV had more frequently a hypocompliant rectum (62%) when compared with those with higher MTV (31%, P = 0.046). Perception scores tended to be higher at each step of distending rectal pressure: incontinent patients with low MTV had more frequently a hypersensitive rectum (48%) when compared with those with normal or high MTV (24%, P = 0.035). Only four of 21 incontinent subjects with low MTV had an isolated hypersensitive rectum.

CONCLUSION

Both sensitivity and compliance are altered in patients with low MTV. A more extensive study of the role of sensory and compliance aspects of subjects with incontinence is warranted.

[Large ossifying fibroma of the jaws and hyperparathyroidism in a chronic hemodialyzed patient]

OBJECTIVE

Describe the exceptional and fortuitous character of the association of ossifying fibroma and hyperparathyroidism in a chronic hemodialyzed patient.

CASE REPORT

A twenty-year-old man who had undergone dialysis for ten years as the result of an indeterminate nephropathy was admitted for a functional disability in the standing position and a serious dysmorphic syndrome with swelling of the jaws that hindered proper closure of the mouth.

RESULTS

Medical imagery revealed a polyostotic attack pleading in favor of renal osteodystrophy or a fibrous dysplasia. The surgical reduction of the tumor of the jaws shown, from the histological viewpoint, a large aggressive ossifying fibroma of the jaws.

CONCLUSION

The association of ossifying fibroma and hyperparathyroidism in a chronic hemodialyzed patient is exceptional and fortuitous. The difficult treatment points out the need for early rigorous prevention of hyperparathyroidism in a chronic hemodialyzed patient.

[Heller's operation in the treatment of idiopathic megaesophagus. Apropos of 35 cases]

The authors report 35 cases of idiopathic megaoesophagus in adult. They underline its clinical latency, often the patients come belatedey the insist upon the interest of Heller's procedure giving the best functional results.