Secretion Of Antidiuretic Hormone In Patients Research Articles

Asymptomatic meningitis diagnosed by positron emission tomography in a patient with syndrome of inappropriate antidiuretic hormone secretion: a case report

BackgroundSyndrome of inappropriate antidiuretic hormone secretion can be caused by arginine-vasopressin-producing tumors or enhanced arginine vasopressin secretion from the posterior pituitary gland due to central nervous system disorders and intrathoracic diseases.Case presentationA 53-year-old Asian man was hospitalized with complaints of tremor and hiccups. Laboratory examination revealed findings suggestive of hypotonic hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion. The patient did not complain of headache or photophobia, and showed no signs of meningeal irritation. Positron emission tomography–computed tomography revealed 18F-fluoro-deoxy-glucose accumulation along the cervical spinal cord, based on which the patient was diagnosed as having aseptic meningitis. The hyponatremia was treated successfully by fluid restriction, and optimum plasma sodium concentration was maintained by tolvaptan administration.ConclusionsThis case underscores the need to consider the possibility of mild meningitis as the cause of syndrome of inappropriate antidiuretic hormone secretion in patients without other identifiable cause.

Syndrome of inappropriate antidiuretic hormone secretion in patients with brucellosis

Introduction: Syndrome of inappropriate antidiuretic hormone secretion (SIADH), is generally characterized by hyponatremia and hypo-osmolarity. Objectives: SIADH may develop following some infectious diseases including brucellosis, which regarding the severity of the disease may cause morbidity or mortality. Patients and Methods: In this case-control study, 110 patients with brucellosis and 110 healthy controls were enrolled. The case group was selected among patients having clinical signs and symptoms of brucellosis with a Wright test titer ≥1/160 and a 2ME test titer ≥1/80. About 10 cc blood sample was taken from each of them to test the blood sugar, thyroid stimulating hormone (TSH), serum sodium, serum potassium, blood urea nitrogen (BUN), creatinine, and serum cortisol. Random urine samples were also taken from participants to measure the urinary osmolarity and sodium. Results: The frequency of hyponatremia (Na <135 mEq/L) in patients with brucellosis was significantly higher than the control group but there was no significant difference between the groups in the frequency of abnormal urinary sodium (more than 40 mEq/L). Meanwhile, the frequency of abnormal uric acid (less than 4 mg/dL) was significantly higher in patients than the control group. The frequency of abnormal urine osmolarity (above 300 mOsm/kg) was significantly higher in patients than the control group. In total, only 9 out of 110 patients had SIADH with asymptomatic mild hyponatremia and severe hyponatremia was seen only in one patient with prolonged Brucella meningitis. Conclusion: Based on the defined criteria, 8.2% of brucellosis patients were at the risk of SIADH, but the findings were in favor of asymptomatic SIADH without prominent hyponatremia.

Hyponatremia in Kawasaki disease: What does it mean and how does it occur?

Kawasaki disease (KD) is an acute febrile vasculitis that predominantly affects children ≤ 5 years of age. The cause of KD remains unknown, but it is thought that the immune system is activated by an infectious trigger in a genetically susceptible host. Because KD is systemic vasculitis, multiple organ involvement can develop, including hyponatremia. Hyponatremia is common in patients with KD, occurring in 29%–70% of patients. Although hyponatremia is usually mild and asymptomatic in nearly all patients with KD, profound hyponatremia contributes to the development of central nervous system dysfunction in some patients. KD patients with hyponatremia have clinical and laboratory findings that are consistent with severe inflammation, including higher C-reactive protein levels and an increased incidence of coronary artery lesions. While the pathogenesis underlying the development of hyponatremia in KD is incompletely understood, several possible mechanisms have been proposed, including hypovolemic hyponatremia, the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), and ingestion of fluid that is hypo-osmolar relative to the fluid loss. Hypovolemic hyponatremia may be caused by gastrointestinal loss of fluid and sodium, and renal loss of fluid and sodium secondary to renal parenchymal injury and/or cytokine-induced renal tubular dysfunction. SIADH occurs in approximately 40% of KD patients with hyponatremia and may be a major cause of hyponatremia in KD. Although the pathogenesis underlying the development of SIADH in patients with KD is unclear, cerebral vasculitis or ADH secretion stimulated by cytokines, including interleukin (IL)-1β and IL-6, may contribute to the development of SIADH in patients with KD.

Syndrome of inappropriate antidiuretic hormone secretion in patients with aquaporin-4 antibody.

The objective of this study was to analyze the frequency of syndrome of inappropriate antidiuretic hormone secretion (SIADH) in patients with positive aquaporin-4 (AQP4) antibodies and evaluate the relationship between SIADH and hypothalamic lesions in patients with NMO and NMO spectrum disorder (NMOSD). AQP4 antibodies were tested by an indirect immunofluorescence assay employing HEK-293 cells transfected with recombinant human AQP4. Clinical data of patients were analyzed retrospectively. In total, 192 patients with AQP4 antibodies were certified, of which 41 patients (21.4 %) were included in the present study. Six patients (14.6 %, 6/41) met the criteria of SIADH, of which hyponatremia was mild in one patient, and severe in five. Five patients experienced confusion or decreased consciousness. Four patients were diagnosed with NMO and two were diagnosed with recurrent optic neuritis. Magnetic resonance imaging showed 11 of 41 patients (26.8 %) had hypothalamic lesions. All patients with SIADH had hypothalamic abnormalities. Hyponatremia resolved in all patients after intravenous methylprednisolone and intravenous immunoglobulin therapy. SIADH is not rare in patients with NMO/NMOSD, especially in patients with lesions close to the hypothalamus.

Syndrome of Inappropriate Antidiuretic Hormone Secretion in Patients with Olfactory Neuroblastoma

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) has been reported as a paraneoplastic syndrome in many different types of malignancies. Several case reports of SIADH have been reported in patients with olfactory neuroblastoma (ONB), but the exact incidence is unknown. The purpose of this study was to review our experience with olfactory neuroblastoma and to identify all patients who had a history of SIADH prior to the diagnosis of ONB. Case series and chart review. Tertiary care university-affiliated medical center. A total of 21 patients presented to our institution with ONB between 1997 and 2009. All records were reviewed for a history of preoperative hyponatremia or SIADH. Three patients were identified who had a history of SIADH prior to the diagnosis of ONB. Immunohistochemical staining of the tumor specimens from the 3 patients with SIADH was positive for arginine vasopressin. SIADH resolved in all 3 patients after successful treatment of ONB. Although uncommon, SIADH can be the presenting symptom of ONB and should be considered during the workup for idiopathic SIADH.

Asian variant of intravascular large B cell lymphoma causes patients to frequently develop the syndrome of inappropriate antidiuretic hormone secretion

The Asian variant of intravascular large B cell lymphoma is a special type of intravascular lymphoma with hemophagocytic syndrome and hypercytokinemia including interleukin-6, which stimulates antidiuretic hormone synthesis in the hypothalamus. We present here that the syndrome of inappropriate antidiuretic hormone secretion frequently occurs in patients with the Asian variant of intravascular large B cell lymphoma. The syndrome of inappropriate antidiuretic hormone secretion was found in eight of 118 (6.8%) lymphoma patients at the first diagnosis. Although there were six (5.1%) among 118 lymphoma patients with the Asian variant of intravascular large B cell lymphoma, four of the six patients (66.7%) developed the syndrome of inappropriate antidiuretic hormone secretion. In four patients with the Asian variant of intravascular large B cell lymphoma with the syndrome of inappropriate antidiuretic hormone secretion, elevated serum interleukin-6 and low sodium levels were almost normalized after chemotherapy. The Asian variant of intravascular large B cell lymphoma patients frequently develop the syndrome of inappropriate antidiuretic hormone secretion, and interleukin-6 might play a role in the occurrence of this disease. We should pay attention to hyponatremia caused by the syndrome of inappropriate antidiuretic hormone secretion in patients with the Asian variant of intravascular large B cell lymphoma.

Guillain-Barré syndrome and SIADH

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in Guillain-Barré syndrome (GBS) is a very often overlooked entity even though it is well-described. However, most of the previous observations are case reports. There are no systematic studies of SIADH in GBS. To assess the incidence and characteristics of SIADH in patients with GBS and to assess whether it is a predictor of poor outcome. We prospectively studied 50 patients with GBS admitted to the Department of Neurology in a tertiary care hospital in South India from January 2009 to April 2010. After obtaining clinical history, electrophysiologic studies were performed to determine the GBS subtype. SIADH was diagnosed based on modified Bartter and Schwartz criteria. SIADH was detected in 24 of the 50 patients (48%) at some stage of the illness (median 8.8 days after GBS onset). Six of them had mild SIADH, 12 patients had moderate SIADH, and 6 patients had severe SIADH. MRC sumscore at the time of admission and discharge was higher in patients with SIADH (p < 0.001) when compared to the normal group. Bulbar weakness and need for ventilatory support were higher in GBS with SIADH (13 vs 1, p < 0.001). Mean duration of hospitalization was longer in SIADH (29.15 vs 10.57, p < 0.001). Most of the patients with GBS with SIADH required plasmapheresis (23 vs 8, p < 0.001). There are 4 variables significantly associated with mortality, which include age >50, ventilatory support, hyponatremia, and bulbar weakness. SIADH is a common and important electrolyte disorder encountered in GBS. It has significant association with severity of GBS and is an indicator of poor prognosis. It can be symptomatic even though the majority of patients are asymptomatic.

The Incidence of Syndrome of Inappropriate Antidiuretic Hormone Secretion in Patients with Esthesioneuroblastoma

Introduction: Esthesioneuroblastoma (ENB) is a rare malignancy of the nasal vault. It is thought to arise from olfactory stem cells of neural crest origin. The most common presenting symptoms include nasal obstruction, rhinorrhea, epistaxis, and headaches. Although ENB is rarely associated with inappropriate antidiuretic hormone secretion, that symptom has been previously described. Recently, two patients presented to our institution with a history of unexplained hyponatremia for several months before detection of ENB.

Comparison of the Frequency and Complications of Inappropriate Antidiuretic Hormone Secretion in Patients with Septic and Aseptic Meningitis

Objective Due to the high prevalence of syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH). This study was carried out to evaluate the prevalence and relevant parameters of SIADH in children with septic and aseptic memingitis hospitalized at Kashan Shahid Beheshti Hospital between 1996 and 2006. Materials & Methods This descriptive study was conducted on 230 patients with meningitis hospitalized in the pediatric wards of Kashan Shahid Beheshti Hospital between 1996 and 2006. Relevant information (age, gender, type of meningitis, serum sodium and potassium, urine specific gravity (USG), blood sugar, blood urea nitrogen, serum creatinin, hydration condition) was collected from patients' records. Data was analyzed using Mann-Whitney and K2 tests. Results Out of 230 patients with meningitis, 33 had incomplete records and only 197 patients were recruited for this study. Sixty eight cases (34.5%) suffered from SIADH. It was more frequent among 1-2 year old children. According to this research, SIADH was diagnosed in 57% of the 121 patients with hyponatremia, 58.7% of the 167 patients with USG > 1.004, 74% of the 93 patients with serum osmolity < 280 mOs/L and 100% of the patients with BUN < 10 mg%. Conclusion Due to the high prevalence of SIADH in septic and aseptic meningitis and its complication, it is recommended to restrict fluid therapy and monitor serum sodium, urine specific gravity and other diagnostic tests for SIADH. Keywords: Hyponatremia; Meningitis; SIADH, Septic, Aseptic

Syndrome of inappropriate secretion of arginine vasopressin in patients with cancer of the head and neck.

The syndrome of inappropriate secretion of arginine vasopressin (AVP) known as the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is associated with a variety of malignant and nonmalignant diseases. Only 17 cases of SIADH have been reported in the literature in association with cancer isolated to the head and neck. A retrospective review of 1,436 patients with head and neck malignancy excluding skin cancer through The University of Iowa Tumor Registry revealed 60 patients with the diagnosis of either SIADH or hyposmolality. A chart review for each of these patients was then done to establish the diagnosis of SIADH through relevant laboratory values and by excluding other causes of hyposmolality and hyponatremia. In 43 of these patients (3%), SIADH was found to be associated only with the cancer of the head and neck. We conclude that the incidence of SIADH in patients with cancer of the head and neck is much higher than previously recognized. As elevated serum AVP levels may not be clinically apparent unless associated with excessive water ingestation, it is possible that an even higher percentage of patients may have increased serum AVP levels.

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in small-cell lung cancer.

Review of clinical data from 350 patients with small-cell lung cancer (SCLC) revealed hyponatremia (sodium less than 130 mEq/L) attributable to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in 40 patients (11%). Although hyponatremia was severe in most instances (median, sodium 117 mEq/L), symptoms attributable to water intoxication were identified in only 27% of hyponatremic episodes. Development of SIADH showed no correlation with clinical stage, distribution of metastatic sites, sex, or histologic subtype of small-cell carcinoma. SIADH occurred most often with initial presentation (33 of 40), and resolved promptly (less than 3 weeks) with initiation of combination chemotherapy in 80% of evaluable patients. The presence of SIADH did not influence response to chemotherapy or overall survival as an independent variable. However, in five patients profound hyponatremia developed immediately following primary cytotoxic therapy (range, one to five days). Despite initial control of SIADH, dilutional hyponatremia recurred in 70% of patients with tumor progression. Our findings suggest that development of clinically demonstrable SIADH in patients with SCLC is dependent on functional properties of the neoplastic cells, rather than tumor burden or metastatic site. The potential for development of clinically significant hyponatremia early in the course of cytotoxic therapy emphasizes the need to closely monitor patients, particularly those receiving chemotherapy regimens requiring substantial intravenous hydration.

SIADH with Hypertensive Cerebral Hemorrhage or Cerebral Infarction

One hundred and five patients with hypertensive cerebral hemorrhage or cerebral infarction were reviewed with regard to the incidence of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). SIADH occurred in 8 (7.6%) out of 105 patients. The mean interval between the onset of cerebrovascular accidents (CVA) and the development of SIADH was 13.9 days (ranging from 7 to 23 days). All the cases with SIADH showed moderate to severe disturbance of consciousness levels. In 2 of these 8 cases, preexisting impaired consciousness was aggravated with severe hyponatremia. The incidence of SIADH varied significantly according to the type of CVA, being lower in cases with cerebral infarction [one out of 51 (1.9%)], than in cases with cerebral hemorrhage [7 out of 54 (12.9%)]. The incidence of SIADH in patients with thalamic hemorrhage (26.7%) was much higher than in patients with putaminal hemorrhage (7.7%). Plasma antidiuretic hormone (ADH) levels measured in 2 cases with SIADH were 8.1 and 6.5 pg/ml, inappropriately elevated for the corresponding serum osmolarities. Even though the mean values of serum sodium and osmolarity were not significantly different from the controls, the mean (±SD) plasma level of ADH in cases with cerebral hemorrhage measured within 14 days after the onset was 7.3±1.6 pg/ml, significantly higher than the controls (p<0.001). Hematological and urinary studies showed that the excessive release of ADH recognized in cases with cerebral hemorrhage was a non-physiological (inappropriate) release of ADH, caused by non-osmotic factors, except blood volume depletion. From the present study, it is suggested that patients with impaired consciousness, especially in an acute stage following cerebral hemorrhage, are unable to suppress ADH release properly to excrete the water load normally, and are susceptible to SIADH even if they are under normoosmotic conditions.