Syndrome of inappropriate secretion of antidiuretic hormone in nasopharynx carcinoma

The syndrome of inappropriate secretion of antidiuretic hormone (ADH) or SIADH has been reported in various disorders. We report a pediatric patient with nasopharynx carcinoma who may have developed a clinical SIADH with severe hyponatremia and generalized seizure during the administration of intravenous hydration. We propose that the inappropriately high plasma level of ADH led to the inability to excrete sufficient amounts of free water during a hyperhydration protocol with a relatively hypotonic fluid, which resulted in acute hyponatremia and central nervous system involvement. To avoid this complication, intravenous hydration before chemotherapy in children with nasopharynx carcinoma should be performed at a slower infusion rate and with a sodium chloride concentration of more than half isotonic.     

Symptomatic syndrome of inappropriate antidiuretic hormone secretion associated with azithromycin

OBJECTIVE: To report a case of symptomatic syndrome of inappropriate antidiuretic hormone (SIADH) secretion associated with azithromycin and review the literature related to this adverse drug reaction. DATA SOURCES: Review articles identified by a computerized (MEDLINE) (1966-April 1996) and manual (Index Medicus) search. DATA SYNTHESIS: Azithromycin is a well-tolerated broad-spectrum macrolide antibiotic. We report a symptomatic case of SIADH secretion associated with azithromycin. The patient received two doses of azithromycin before the development of sudden mental status changes associated with severe hyponatremia. All other potential causes were ruled out. No previous reports exist in the literature. CONCLUSIONS: Azithromycin may be associated with symptomatic SIADH secretion. Awareness and attention are required if patients develop mental status changes or hyponatremia while receiving azithromycin so that appropriate diagnostic and therapeutic actions can be implemented.     

Bilateral pneumonia and inappropriate secretion of antidiuretic hormone in a premature infant

A 6-week-old infant born prematurely had severe hyponatremia and other features of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). This disturbance was believed to be secondary to extensive bilateral pneumonia with collapse of the right upper lobe. Although this association has been recognized in adults, this is the first report of its occurrence in an infant. SIADH must be considered in the differential diagnosis of hyponatremia in association with pneumonia in an infant.     

Asymptomatic hyponatremia due to inappropriate secretion of antidiuretic hormone as the first sign of a small cell lung cancer in an elderly man

A 72-year-old man was hospitalized with asymptomatic hyponatremia. Despite hyponatremia, urinary sodium excretion with urine osmolality exceeding plasma osmolality persisted. Plasma vasopressin levels were high and independent of plasma osmolality during hypertonic saline infusion. Computed tomography of the chest showed enlarged mediastinal and right hilar lymph nodes. Microscopically, a specimen of lymph nodes obtained by biopsy represented vasopressin-producing small cell lung carcinoma. Chemotherapy plus irradiation improved the hyponatremia. Thus, careful evaluation is necessary to determine the cause of hyponatremia disorders in elderly patients.     

Development of syndrome of inappropriate secretion of antidiuretic hormone during progression of metastatic breast cancer

A patient who developed syndrome of inappropriate secretion of antidiuretic hormone (SIADH) during progression of metastatic breast cancer is described. The classic criteria for SIADH as defined by Bartter and Schwartz were fulfilled and conditions other than malignant disease were excluded as causes of the syndrome. To the knowledge of the authors SIADH has never been reported to develop during the course of malignant disease in a patient with metastatic breast cancer. It should be borne in mind that SIADH may occur in patients with malignant disease and hyponatraemia, even in the absence of small-cell lung cancer, which is the classic tumour type to develop SIADH.     

Syndrome of inappropriate antidiuretic hormone associated with vinorelbine therapy

OBJECTIVE: To describe onset of syndrome of inappropriate antidiuretic hormone (SIADH) associated with vinorelbine therapy for advanced breast cancer. CASE SUMMARY: A 50-year-old white woman with a history of advanced breast cancer refractory to other treatment modalities was receiving vinorelbine. Blood chemistries revealed severely depleted sodium and potassium concentrations from a normal baseline within a 7-day period. A recheck of blood chemistries confirmed hyponatremia. The patient was admitted to the hospital and treated for SIADH. After successful treatment, she was given demeclocycline prophylactically and rechallenged with vinorelbine without recurrence of the syndrome. DISCUSSION: SIADH has been reported as a complication of treatment with vinca alkaloids. To our knowledge, this is the first report of this syndrome related to vinorelbine therapy. CONCLUSIONS: Because of its structural similarity to the other vinca alkaloids, vinorelbine is believed to be responsible for SIADH in our patient. Clinicians should be aware of the possibility that vinorelbine may cause SIADH and possibly hypokalemia.     

Hyponatremia and the syndrome of inappropriate secretion of antidiuretic hormone associated with the use of selective serotonin reuptake inhibitors: a review of spontaneous reports

OBJECTIVE: To review reported cases of hyponatremia and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with the use of selective serotonin reuptake inhibitors (SSRIs). DATA SOURCES: A search of MEDLINE for reports of hyponatremia and SIADH associated with the use of fluoxetine, fluvoxamine, paroxetine or sertraline published between January 1980 and May 1995. Unpublished reports of cases were requested from the pharmaceutical industry, the Ontario Medical Association, the Health Protection Branch of Health Canada, the US Food and Drug Administration and the World Health Organization. DATA SELECTION AND EXTRACTION: Spontaneous reports from postmarketing surveillance. DATA SYNTHESIS: A total of 736 cases of hyponatremia [corrected] and SIADH associated with SSRI use were reported. Fluoxetine was involved in 554 (75.3%) of the cases, paroxetine in 91 (12.4%), sertraline in 86 (11.7%) and fluvoxamine in 11 (1.5%). Reports of 30 cases were published. The remaining 706 cases were reported to monitoring bodies and the pharmaceutical industry. According to information in the published reports, the median time to onset of hyponatremia was 13 days (range 3 to 120 days). Most (83%) of the published cases involved patients 65 years of age or more, as compared with 74% of the unpublished cases. CONCLUSION: Elderly people may be at increased risk for hyponatremia associated with SSRI use. Physicians caring for elderly patients should be aware of this potentially serious but reversible adverse effect. Further research is required to determine the incidence of this adverse effect, the relative risk of hyponatremia and SIADH in different age groups and the risk associated with different SSRI drugs.     

The syndrome of inappropriate secretion of antidiuretic hormone: an unusual presentation for childhood craniopharyngioma: report of three cases

OBJECTIVE AND IMPORTANCE: Childhood craniopharyngiomas may present with variable endocrine dysfunctions. However, hyponatremia secondary to the syndrome of inappropriate secretion of antidiuretic hormone has never been reported. We describe three children with craniopharyngioma who presented with hyponatremia. CLINICAL PRESENTATION: Three children had hyponatremia at presentation, two of whom had experienced generalized seizures. Urine sodium levels measured in two patients were abnormally high. Neuroimaging tests, including computed tomography and magnetic resonance imaging, showed a large partially calcified and partially cystic craniopharyngioma in the sellar/suprasellar location. INTERVENTION: Intake of fluids was restricted for each patient, with improvement of hyponatremia, and each patient subsequently underwent a successful tumor resection. Postoperatively, all patients developed panhypopituitarism, including diabetes insipidus, and needed multiple hormonal replacement therapy. CONCLUSION: Endocrine dysfunctions at diagnosis are commonly associated with childhood craniopharyngiomas, but the association of the syndrome of inappropriate secretion of antidiuretic hormone with craniopharyngioma has never been reported. Craniopharyngiomas should be included as a possibility in making the differential diagnosis of the syndrome of inappropriate secretion of antidiuretic hormone in children.     

Neuropsychiatric systemic lupus erythematosus and the syndrome of inappropriate secretion of antidiuretic hormone: a case report with very late onset systemic lupus erythematosus

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) associated with neuropsychiatric lupus (NP-SLE) is rare. We report a case of SIADH associated with the new onset of SLE in an 88-yr-old female. The unique features of this case include the extreme age of onset of SLE presenting with neuropsychiatric manifestations and positive antiribosomal P antibody titres. Both the NP manifestations of SLE and SIADH were highly correlated with the SLE disease activity. This case illustrates a novel presentation of NP-SLE with SIADH which may develop due to antibody-mediated hypothalamic dysfunction.     

Inappropriate antidiuretic hormone secretion. Occurrence in a patient with Rocky Mountain spotted fever

A 51-year-old man with serologically confirmed Rocky Mountain spotted fever was believed to have inappropriate antidiuretic hormone (ADH) secretion. He was observed for four days in the hospital until the correct diagnosis was made. During this period, he progressively became more hyponatremic, despite a low BUN level and the administration of large amounts of sodium and water. At the time, his serum sodium concentration was 117 mEq/liter, and his urine was hypertonic to that of serum. Thereafter, his serum sodium level rose with fluid restriction. Rickettsia-induced CNS damage may have lead to the inappropriate ADH release that was observed in this patient.     

Inappropriate secretion of antidiuretic hormone (SIADH) in a patient with pleurisy related to adult onset Still''s disease

OBJECTIVE: To assess the prevalence of self-treatment in men with new episode non gonococcal urethritis (NGU). METHOD: Three hundred consecutive men with new episode NGU attending an open access genitourinary medicine clinic were interviewed using a semi-structured questionnaire. Details of treatment used before attending the clinic were obtained. RESULTS: Thirty (10%) men had used treatment, for an average of 7 days, prior to the clinic attendance. Agents used included antibiotics (11), savion or iodine (4), vitamin tablets (4), cisapride (2), local anaesthetic gel (2), antiseptic cream (2), cod liver oil (1), ferrous sulphate (1), naproxen (1), clotrimazole cream (1) and a poultice (1). Over 70% of the men reporting antibiotic use had self-medicated and in one case a fixed drug eruption had ensued. CONCLUSION: A significant number of men with NGU self-treat. In addition to the adverse effects of such treatment and the potential effect on culture tests, clinic attendance may be postponed, the use of appropriate therapy delayed, and sexual contacts will remain at risk. Early attendance for treatment and contact tracing is essential and should be actively promoted.