Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in malignant disease

Abstract

. The first clinical case of a patient with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) was presented by Schwartz et al. in 1957 (Am J Med 1957; 23: 529–42), describing two patients with lung cancer who developed hypo‐natraemia associated with continued urinary sodium loss. They postulated that the tumours led to the inappropriate release of antidiuretic hormone (ADH), later discovered to consist of arginine‐vasopressin (AVP). This suggestion was later confirmed in several studies. The clinical description of the syndrome has changed little since the original observation, and the cardinal findings of SIADH are as follows: (i) hyponatremia with corresponding hypo‐osmolality of the serum and extracellular fluid, (ii) continued renal excretion of sodium, (iii) absence of clinical evidence of fluid volume depletion, (iv) osmolality of the urine greater than that appropriate for the concomittant osmolality of the plasma, i.e. urine less than maximal diluted, and (v) normal function of kidneys, suprarenal glands and thyroid glands. Measurement of AVP in plasma is not a part of the definition of SIADH. SIADH may be caused by a variety of malignant tumours, but may also be caused by various other conditions, such as disorders involving the central nervous system, intrathoratic disorders such as infections, positive pressure ventilation and conditions with decrease in left atrial pressure. Also, a large number of pharmaceutical agents have been shown to produce SIADH, including a number of cytotoxic drugs such as vincristine, vinblastine, cisplatin, cyclophosphamide, and melphalan. A broad spectrum of malignant tumours has been reported to cause SIADH; however, most of these observations have been in case reports including very few patients. This includes a number of primary brain tumours, haematologic malignancies, intrathoracic non‐pulmonary cancers, skin tumours, gastrointestinal cancers, gynaecological cancer, breast‐and prostatic cancer, and sarcomas. Larger series of patients have revealed that SIADH occurs in 3% of patients with head and neck cancer (47 cases out of 1696 patients), in 0.7% of patients with non‐small‐cell lung cancer (three cases out of 427 patients), and in 15% of cases of small‐cell lung cancer (214 cases out of 1473 patients). The optimal therapy for SIADH is to treat the underlying malignant disease. If this is not possible, or if the disease has become refractory, other treatment methods are available such as water restriction, demeclocycline therapy, or, in severe cases, infusion of hypertonic saline together with furosemide during careful monitoring.

Hyponatremia and syndrome of inappropriate antidiuretic hormone secretion complicating stem cell transplantation

“…Hyponatremia related to SIADH has been associated with various antineoplastic agents, including vincristine, CY, ifosfamide, and thiotepa. 10,11 However, our analysis showed that drugs and radiation used during conditioning were not associated with SIADH. SIADH has also been reported to be associated with several hematological diseases such as NHL and Hodgkin's disease.…”

Hyponatraemia—Evaluation of Prevalence in Patients Hospitalized in the Pulmonary Department and Prognostic Significance in Lung Cancer Patients

“…It is estimated that SIADH occurs in 15% of patients with SCLC and in 0.7% of patients with NSCLC. Other neoplasms that coexist with hyponatraemia are first of all carcinomas of the head and neck (3%), primary and metastatic tumours of the CNS, breast carcinoma, haematological malignancies (lymphomas, chronic lymphocytic leukaemia, multiple myeloma) and many others [13]. SIADH is also diagnosed in the course of many nonneoplastic diseases: in CNS diseases (traumas, meningitis, encephalitis, postoperative states), psychoses and benign diseases of the lung and pleura -in pleuritis, pneumonia, tuberculosis, empyema and asthma.…”

“…While looking for other causes of hyponatraemia in cancer patients it should be remembered that stress and pain may be important contributing factors [13].…”

Iatrogenic Water Intoxication in A Persian Cat: A Case Report

“…TURP is surgical manipulation which highly risks water intoxication post-surgically. SIADH is common in humans suffering from multiple tumors (Talmi et al, 1992;Sorensen et al, 1995), however evaluation of patient's anamnesis didn't bring out any associated tumor and surgical manipulation. Furthermore, urinanalysis of cat didn't reveal any significant changes as the patients of SIADH are usually characterized by more concentrated and less volume urine (Dibartola, 2012).…”