[Afferent baroreflex failure with hyponatremia: A case report].

Afferent baroreflex failure (ABF) is a rare disease. It refers to the clinical syndrome caused by the impairment of the afferent limb of the baroreflex or its central connections at the level of the medulla. The recognized causes include trauma, surgery in related areas (radical neck tumor surgery, carotid endarterectomy), neck radiotherapy, brain stem stroke, tumor growth paraganglioma and hereditary diseases, among which the most common cause is extensive neck surgery or radiotherapy for neck cancer. The main manifestations are fluctuating hypertension, orthostatic hypotension, paroxysmal tachycardia and bradycardia. This case is a young man, whose main feature is blood pressure fluctuation, accom-panied by neurogenic orthostatic hypotension (nOH). After examination, the common causes of hypertension and nOH were ruled out. Combined with the previous neck radiotherapy and neck lymph node dissection, it was considered that the blood pressure regulation was abnormal due to the damage of carotid sinus baroreceptor after radiotherapy for nasopharyngeal carcinoma and neck lymph node dissection, which was called ABF. At the same time, the patient was complicated with chronic hyponatremia. Combined with clinical and laboratory examination, the final consideration was caused by syndrome of in- appropriate antidiuretic hormone (SIADH). Baroreceptors controlled the secretion of heart rate, blood pressure and antidiuretic hormone through the mandatory "inhibition" signal. We speculate that the carotid sinus baroreceptor was damaged after neck radiotherapy and surgery, which leads to abnormal blood pressure regulation and nOH, while the function of inhibiting ADH secretion was weakened, resulting in higher ADH than normal level and mild hyponatremia. The goal of treating ABF patients was to reduce the frequency and amplitude of sudden changes in blood pressure and heart rate, and to alleviate the onset of symptomatic hypotension. At present, drug treatment is still controversial, and non-drug treatment may alleviate some patients' symptoms, but long-term effective treatment still needs further study. The incidence of ABF is not high, but it may lead to serious cardiovascular and cerebrovascular events, and the mechanism involved is extremely complicated, and there are few related studies. The reports of relevant medical records warn that patients undergoing neck radiotherapy or surgery should minimize the da-mage to the baroreceptor in the carotid sinus in order to reduce the adverse prognosis caused by complications.

Syndrome of inappropriate antidiuretic hormone release secondary to central nervous system coccidioidomycosis with vasculitis.

A man in his 60s presented to the clinic due to night sweats and weight loss following pneumonia. He was found to have hyponatraemia due to a syndrome of inappropriate antidiuretic hormone (SIADH). CT of the thorax was concerning for pulmonary nodules. He was ultimately diagnosed with pulmonary coccidioidomycosis (CM) and started on fluconazole 400 mg daily with improvement in symptoms. Due to the report of headaches, head MRI was conducted which suggested central nervous system (CNS) involvement. Cerebrospinal fluid analysis was consistent with CNS CM and head magnetic resonance angiography confirmed the presence of CNS vasculitis. Fluconazole dose was increased to 800 mg daily which the patient continued to tolerate and showed improvement. This report depicts a case of SIADH associated with CNS CM with vasculitis and demonstrates the importance of high clinical suspicion for SIADH secondary to CNS CM in the setting of hyponatraemia and headache.

Severe hyponatremia and diabetes insipidus caused by low-dose cyclophosphamide in breast cancer patients: A case report and literature review.

RATIONALE: Cyclophosphamide (CTX) is widely used in the treatment of malignancies and autoimmune diseases. Although severe hyponatremia caused by low-dose CTX chemotherapy is uncommon, it can lead to serious complications and even death. PATIENT CONCERNS: A 44-year-old woman with left-sided breast cancer suddenly experienced headaches, disorientation and weakness after receiving low-dose neoadjuvant chemotherapy combined with CTX and doxorubicin. DIAGNOSES: The patient pathology showed invasive breast carcinoma. She developed severe hyponatremia and a generalized seizure after completing the first cycle of neoadjuvant chemotherapy with CTX and doxorubicin. Laboratory tests showed a serum sodium of 118 mmol/L (normal range 135-145 mmol/L) and potassium sodium 3.16 mmol/L (normal range 3.5-5.5 mmol/L). Subsequently, the patient developed secondary diabetes insipidus 4 hours after sodium supplementation, her 24-hour urine volume was 4730 mL (normal range 1000-2000 mL/24 hours), and the urine specific gravity decreased to 1.005. INTERVENTIONS: The patient was given intravenous sodium chloride (500 mL of 3%NaCl, 100 mL/hour) and potassium chloride (500 mL of 0.3%KCl, 250 mL/hour). Meanwhile, she was advised to reduce her water intake, and pituitrin was administered to prevent dehydration caused by diabetes insipidus. OUTCOMES: The patient completely recovered after correcting of the serum sodium concentration (137 mmol/L) without any neurological deficits. After discontinuing pituitrin, her 24-hour urine volume was 2060 mL and the urine specific gravity was 1.015. LESSONS: This is a typical case of severe hyponatremia induced by low-dose CTX. Clinicians and healthcare providers should be aware of this potential toxicity, and appropriate monitoring should be implemented.

Midodrine reduces new-onset acute kidney injury and hyponatremia in children with cirrhosis and ascites awaiting liver transplantation: Results from an open-label RCT.

OBJECTIVES: Midodrine, an oral α-1-adrenergic receptor agonist, counters arterial hypovolemia and reduces complications in adult patients with cirrhosis. This randomized controlled trial (RCT) aimed to assess the efficacy and safety of midodrine in preventing complications and improving survival in children with cirrhosis and ascites who are awaiting liver transplantation (LT). METHODS: This open-label RCT conducted from January 2022 to May 2023 included children under 18 years with cirrhosis and ascites. Patients were randomized to receive either midodrine plus standard medical therapies (SMTs) or SMT alone. The primary outcome measure was the incidence of cirrhosis-related complications within 6 months. RESULTS: Thirty-five subjects were enrolled and randomized. Patients in the midodrine arm had a lower incidence of new-onset acute kidney injury (AKI) compared with the SMT arm (11.1% vs. 41.2%). Patients in the midodrine arm showed a decline in serum creatinine and improvement in glomerular filtration rate, whereas no changes were observed in the SMT arm. There was a lower incidence of new-onset hyponatremia in the midodrine arm (20% vs. 56%). Midodrine led to reduction in plasma rennin activity (PRA) and improvement in systemic hemodynamics. There was no difference in the rate of resolution of ascites, recurrence of ascites, requirement of therapeutic paracentesis, cumulative albumin infusion requirement, episodes of spontaneous bacterial peritonitis, and hepatic encephalopathy between the two arms. CONCLUSION: Midodrine, when added to SMT, was effective in reducing the incidence of new-onset AKI and hyponatremia in pediatric cirrhotics awaiting LT. It also improved systemic hemodynamics and showed a trend towards reducing PRA.

New onset of isolated adrenocorticotropin deficiency associated with encephalopathy following coronavirus disease 2019 in a healthy elderly man.

Coronavirus disease 2019 (COVID-19) due to a severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection can include various systemic organ disorders including endocrinopathies and neurological manifestations. We report the case of a 65-year-old Japanese man who developed isolated adrenocorticotropic hormone (ACTH) deficiency and encephalopathy following SARS-CoV-2 infection. Two weeks after his COVID-19 diagnosis, he was emergently admitted to our hospital because of subacute-onset delirium. On admission, he presented hyponatremia (128 mEq/L) and secondary adrenal insufficiency (ACTH <1.5 pg/mL, cortisol 0.53 µg/dL). Brain imaging and laboratory examinations including SARS-CoV-2 polymerase chain reaction testing in the cerebrospinal fluid revealed no abnormalities. His consciousness level worsened despite the amelioration of hyponatremia by intravenous hydrocortisone (100 mg/day), but his neurological presentations completely resolved after three consecutive days of high-dose (400 mg/day) hydrocortisone. His encephalopathy did not deteriorate during hydrocortisone tapering. He continued 15 mg/day hydrocortisone after discharge. His encephalopathy might have developed via a disturbance of the autoimmune system, or a metabolic effect associated with adrenal insufficiency, although the time lag between the hyponatremia's improvement and the patient's neurological response to the steroid was incompatible with common cases of delirium concurrent with adrenal insufficiency. At 13 months after his hospitalization, the patient's neurological symptoms have not recurred and he has no endocrinological dysfunctions other than the remaining ACTH deficiency. A thorough consideration of the immunological and metabolic characteristics of SARS-CoV-2 is advisable when clinicians treat patients during and even after their COVID-19 disease period.

COVID-19 and outcomes in Chinese peritoneal dialysis patients.

BACKGROUND: Reports on COVID-19 in peritoneal dialysis (PD) patients are scarce in China. This study aimed to describe the characteristics and outcomes of PD patients with COVID-19 after China abandoned the 'zero-COVID' policy. METHODS: This single-centre retrospective study included patients receiving PD who underwent testing for COVID-19 infections between 7 December 2022 and 7 January 2023. Outcomes of interest included factors associated with positive COVID-19 testing result and clinical outcomes including COVID-19-related hospitalisation and severe COVID-19, which were analysed using logistic regression analyses. RESULTS: A total of 349 PD patients (male 53.6%, age 49 ± 13 years old) were included, and 235 patients (67.3%) were infected. There were no significant differences between COVID-19 and non-COVID-19 patients other than higher proportion of vaccinated patients and slow transporters in the patients who tested positive for COVID-19 (44.7% vs. 28.1%, p = 0.003; 8.7% vs. 1.8%, p = 0.03, respectively). Multivariate analysis showed COVID-19 was associated with vaccination (odds ratio (OR): 1.71, 95% confidence interval (CI): 1.02-2.86) and slow transport type (compared with average transport type, OR: 4.52, 95% CI: 1.01-20.21). Among the patients with infection, 38 (16.2%) patients were hospitalised, 18 (7.7%) patients had severe disease and 9 (3.8%) patients died. In multivariate logistic analysis, both age (OR: 1.04, 95% CI: 1.01-1.07; OR: 1.06, 95% CI: 1.02-1.11) and hyponatremia (OR: 5.44, 95% CI: 1.63-18.13; OR: 6.50, 95% CI: 1.77-23.85) were independent risk factors for COVID-19-related hospitalisation and severe disease. CONCLUSIONS: Although vaccinated patients were more likely to have tested positive for COVID-19 infection, they appeared to have less severe infection and less need for hospitalisation. Patients who were older with a history of hyponatremia were more likely to experience adverse outcomes from COVID-19.

The syndrome of inappropriate antidiuretic hormone associated with nasal and paranasal malignant tumors.

PURPOSE: To investigate the clinical characteristics of the syndrome of inappropriate antidiuretic hormone (SIADH) associated with nasal and paranasal malignant tumors. METHODS: Patients with locally advanced or recurrence/metastatic malignant tumors of the nasal and paranasal sinuses were included. The SIADH was diagnosed according to the diagnostic criteria. The clinical characteristics of SIADH patients were retrospectively analyzed. RESULTS: Six patients (6/188, 3.2%) met the diagnostic criteria of SIADH, including four olfactory neuroblastoma (4/26, 15.4%), one neuroendocrine carcinoma (1/9, 11.1%), and one squamous cell carcinoma (1/63, 1.6%). Five patients (83.3%) had severe hyponatremia; however, the hyponatremia could be improved by fluid restriction or tolvaptan. Three patients' SIADH were recovered during the chemotherapy and the other three were recovered after the surgery. CONCLUSION: The incidence of SIADH associated with nasal and paranasal malignant tumors is relatively more common in olfactory neuroblastoma and neuroendocrine carcinoma. The hyponatremia caused by SIADH may be corrected by fluid restriction or tolvaptan, and the SIADH may be recovered through anti-tumor therapy.

Hyponatremia is associated with unfavorable outcomes after reperfusion treatment in acute ischemic stroke.

BACKGROUND AND PURPOSE: In patients with acute ischemic stroke, hyponatremia (plasma sodium < 136 mmol/L) is common and associated with unfavorable outcomes. However, data are limited for patients who underwent intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT). Therefore, our aim was to assess the impact of hyponatremia on postreperfusion outcomes. METHODS: We analyzed data of consecutive patients who presented with acute ischemic stroke and were treated with IVT and/or EVT at Isala Hospital, the Netherlands, in 2019 and 2020. The primary outcome measure was the adjusted common odds ratio (acOR) for a worse modified Rankin Scale (mRS) score at 3-month follow-up. Secondary outcomes included symptomatic intracranial hemorrhage, in-hospital mortality, infarct core, and penumbra volumes. RESULTS: Of the 680 patients (median age = 73 years, 49% female, median National Institutes of Health Stroke Scale = 5), 430 patients (63%) were treated with IVT, 120 patients (18%) with EVT, and 130 patients (19%) with both. Ninety-two patients (14%) were hyponatremic on admission. Hyponatremia was associated with a worse mRS score at 3 months (acOR = 1.76, 95% confidence interval [CI] = 1.12-2.76) and in-hospital mortality (aOR = 2.39, 95% CI = 1.23-4.67), but not with symptomatic intracranial hemorrhage (OR = 1.17, 95% CI = 0.39-3.47). Hyponatremia was also associated with a larger core (17.2 mL, 95% CI = 2.9-31.5) and core to penumbra ratio (55.0%, 95% CI = 7.1-102.9). CONCLUSIONS: Admission hyponatremia in patients with acute ischemic stroke treated with IVT and/or EVT was independently associated with unfavorable postreperfusion outcomes, a larger infarct core, and a larger core to penumbra ratio. Future studies should address whether correction of hyponatremia improves the prognosis.

Hyponatremia and takotsubo syndrome: a review of pathogenetic and clinical implications.

Hyponatremia is a common electrolyte abnormality with important prognostic and therapeutic implications. It might exert detrimental effects on various organ systems including the central nervous system (CNS), bone, and heart along with its potential association with poor quality of life. These adverse effects might be largely mediated through a variety of mechanisms including osmotic stress, dysfunctional transmembrane exchangers, and enhanced oxidative stress.Interestingly, hyponatremia might also have an important association with takotsubo syndrome (TTS) that has been universally considered as a reversible form of cardiomyopathy usually emerging in response to various stressors. In this context, severe hyponatremia was previously reported to serve as a direct trigger of TTS evolution largely through its potential impact on CNS and heart. However, pathogenetic and clinical implications of hyponatremia still need to be thoroughly evaluated in patients with TTS. This paper aims to analyze the clinical features of published cases with TTS primarily triggered by hyponatremia and also aims to discuss the association between hyponatremia and TTS from a broader perspective.

Association of admission serum sodium and outcomes following out-of-hospital cardiac arrest.

BACKGROUND: The prognostic association between dysnatremia and outcomes in out-of-hospital cardiac arrest (OHCA) is not well understood. Given hypernatremia is associated with poor outcomes in critical illness and hyponatremia may exacerbate cerebral edema, we hypothesized that dysnatremia on OHCA hospital admission would be associated with worse neurological outcomes. METHODS: We studied adults (≥19 years) with non-traumatic OHCA between 2009 and 2016 who were enrolled in the British Columbia Cardiac Arrest Registry and survived to hospital admission at 2 quaternary urban hospitals. We stratified cases by admission serum sodium into hyponatremic (<135 mmol/L), normonatremic (135-145 mmol/L), and hypernatremic (>145 mmol/L) groups. We used logistic regression models, adjusted for age, sex, shockable rhythm, admission serum lactate, and witnessed arrest, to estimate the association between admission sodium and favorable neurological outcome (cerebral performance category 1-2 or modified Rankin scale 0-3). RESULTS: Of 414 included patients, 63 were hyponatremic, 330 normonatremic, and 21 hypernatremic. In each respective group, 21 (33.3%), 159 (48.2%), and 3 (14.3%) experienced good neurological outcomes. In univariable models, hyponatremia (OR 0.53, 95% CI 0.30-0.93) and hypernatremia (OR 0.19, 95% CI 0.05-0.65) were associated with lower odds of good neurological outcomes compared to the normonatremia group. After adjustment, only hypernatremia was associated with lower odds of good neurological outcomes (OR 0.22, 95% CI 0.05-0.98). CONCLUSIONS: Hypernatremia at admission was independently associated with decreased probability of good neurological outcomes at discharge post-OHCA. Future studies should focus on elucidating the pathophysiology of dysnatremia following OHCA.

Postpartum acute adrenal insufficiency of early-onset Sheehan syndrome: A case series study in a single center.

AIM: To identify the symptoms and relevant factors associated with acute adrenal insufficiency of early-onset Sheehan syndrome. METHODS: We retrospectively reviewed the charts of 125 women admitted to our intensive care unit because of postpartum hemorrhage between January 2011 and December 2021. Three women developed acute adrenal insufficiency. We investigated the total blood loss, shock status, consciousness level upon arrival, and intensive care provided to the women. We also analyzed the symptoms and laboratory data that led to the diagnosis of acute adrenal insufficiency. Continuous variables were presented by median (minimum-maximum). RESULTS: The medians and ranges of age, total blood loss, and shock index [heart rate/systolic blood pressure] on admission were 33.1 (17.2-45.3) years, 3351 (595-20 260) g, and 0.94 (0.55-2.94), respectively. Seven women were older than 40 years, 28 experienced >5000 g blood loss, 17 had shock index >1.5, 27 had impaired consciousness upon arrival, and 15 underwent hysterectomy. Women who developed acute adrenal insufficiency were <40 years old and had a bleeding volume of over 5000 g, impaired consciousness upon arrival, and had undergone hysterectomy. They had experienced lactation failure, presented with hyponatremia-related symptoms on postpartum days 8-9, experienced general malaise, headache, and impaired consciousness, and showed severe hyponatremia. CONCLUSIONS: Massive postpartum hemorrhage over 5000 g, impaired consciousness upon arrival, and hysterectomy as a hemostatic measure were relevant factors associated with acute adrenal insufficiency of early-onset Sheehan syndrome. Hyponatremia-related symptoms occurring after lactation failure are indicative of the onset of acute adrenal insufficiency.

Impact of Medical and Neurologic Complications on the Outcome of Patients with Aneurysmal Subarachnoid Hemorrhage in a Middle-Income Country.

OBJECTIVE: Almost two thirds of the world's aneurysmal subarachnoid hemorrhage (aSAH) are in low- and middle-income countries. Herein, we aimed to evaluate the impact of complications on the outcome of aSAH in a middle-income country. METHODS: Baseline data (age, sex, World Federation of Neurosurgical Society, time ictus-treatment, treatment modality) and medical and neurologic complications from a cohort in Brazil (2016-2019) were evaluated: delayed cerebral ischemia; hydrocephalus; meningitis; seizures; intracranial hypertension; infections (pneumonia, bloodstream, urinary tract infection infection of undetermined source); sodium disturbances; acute kidney injury; and cardiac and pulmonary complications. The primary outcome was the modified Rankin scale (mRS) at hospital discharge. Univariate and multivariate models were employed. RESULTS: From 212 patients (71.7% female, age 52.7 ± 12.8), 92% developed at least 1 complication (any infection-43.9%, hydrocephalus-34.4%, intracranial hypertension-33%, infection of undetermined source-20.8%, hypernatremia-20.8%, hyponatremia-19.8%, delayed cerebral ischemia-related infarction-18.7%, pneumonia-18.4%, acute kidney injury-16.5%, and seizures-11.8%). In unadjusted analysis, all but hyponatremia and urinary tract infection were associated with mRS 3-6 at discharge; however, complications explained only 12% of the variation in functional outcome (mRS). Most patients were treated by clipping (66.5%), and 15.6% (33 patients) did not receive a definitive treatment. The median time ictus-admission and ictus-treatment were 5 and 9 days, respectively. CONCLUSIONS: While medical and neurologic complications are a recognized opportunity to improve aSAH care, low- and middle-income countries comprise 70% of the world population and still encounter difficulties concerning early definitive aneurysm treatment, rebleeding, and human and material resources.

Effect of mild hyponatremia on in-hospital falls of elderly hospitalized patients: A retrospective, cohort study.

OBJECTIVES: This study investigated the association between hyponatremia and falls in elderly hospitalized patients, focusing on mild hyponatremia as a potential risk factor. MATERIALS AND METHODS: A retrospective analysis of 16,952 patients admitted to Kochi Medical School Hospital from 2012 to 2021 was performed. Serum sodium levels were categorized, and falls during a 30-day observation period were recorded. A Cox proportional hazards model and a machine learning model were used to estimate risk and explore interactions. RESULTS: Mild hyponatremia (130-134 mEq/L) was identified as an independent risk factor for falls (hazard ratio: 1.42, 95 % confidence interval 1.16-1.74), especially in patients with higher activities of daily living. The fall prediction model showed an area under the curve (AUC) of 0.780 (95 % confidence interval 0.751-0.806). CONCLUSION: A significant association between mild hyponatremia and falls in elderly hospitalized patients was found. The findings highlight the need for targeted fall prevention and further research into the underlying mechanisms. Mild hyponatremia may serve as a clinical marker for fall risk, especially in patients with independent activities of daily living.

Hyponatremia as a Prognostic Factor in Advanced Stage Ovarian Cancer Patients.

Background: hyponatremia represents one of the most commonly encountered conditions in hospitalized patients, multiple mechanisms being cited so far, neoplastic syndromes being an important cause. The aim of the current paper is to analyse the presence and influence of the short- and long-term outcomes of hyponatremia on ovarian cancer patients submitted to surgery for advanced stage ovarian cancer. Method: 57 patients diagnosed with advanced stage ovarian cancer were submitted to surgery between 2014-2020. The patients were further classified according to the preoperative value of sodium into two groups. Results: there were 21 cases with preoperative normal values of sodium and respectively 36 cases with hyponatremia. Patients with preoperative hyponatremia associated a significantly higher rate of early postoperative complications and a significantly poorer long-term outcome. Therefore, cases with hyponatremia reported a mean disease-free survival of 10.8 months and respectively a mean overall survival of 18.5 months while cases with normal natrium levels reported a mean disease-free survival of 31.4 months and respectively a mean overall survival of 49.7 months (p=0.0001 and p 0.001). Conclusions: patients with lower preoperative values of sodium have a higher risk of developing postoperative complications and a significantly poorer outcome when compared to cases presenting normal levels of sodium preoperatively.

Hypothalamic Injury and Clinical Outcomes in Patients with Post-Traumatic Hyponatremia: A Diffusion Tensor Imaging Case-Control Study.

BACKGROUND Diffusion tensor imaging (DTI) is an advanced magnetic resonance imaging (MRI) method used to identify changes in microstructures in the brain's white matter. Severe brain injuries after trauma are associated with disorders of consciousness (DOC) and may result in hyponatremia due to damage to the hypothalamus. This case-control study aimed to use DTI to evaluate the hypothalamus in 36 patients with hyponatremia and DOC due to severe brain injuries. MATERIAL AND METHODS Thirty-six patients with DOC after traumatic brain injury (TBI) and 36 healthy control subjects were enrolled in this study. The diagnosis of DOC was based on the coma recovery scale-revised (CRS-R). The 36 patients were divided into 2 groups: Group A (18 with hyponatremia, serum sodium level <135 mmol/L) and group B (18 without hyponatremia). The DTI scans were conducted using a 6-channel head coil on a 1.5T Philips Gyroscan Intera scanner. Among the DTI data, fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) of the hypothalamus were analyzed. RESULTS Patient group A had a lower FA value (P=0.044) and higher ADC value (P=0.004) of the hypothalamus and showed a longer length of hospital stay (P=0.03), lower CRS-R score at discharge (P=0.01), and less change in CRS-R score (P=0.004) compared to patient group B. The improvements in the CRS-R score revealed a moderate negative correlation (r=-0.467) with the severity of the hyponatremia (P=0.004). CONCLUSIONS Post-traumatic hyponatremia was associated with hypothalamic injury and the presence and severity of hyponatremia were associated with poor clinical outcomes in DOC patients.

Usefulness of serum sodium levels as a novel marker for predicting acute appendicitis severity: a retrospective cohort study.

BACKGROUND: Early and accurate preoperative diagnosis of complicated appendicitis mandates the identification of new markers. The aim of this study is to determine whether preoperative serum sodium levels are useful for predicting the severity of acute appendicitis. METHODS: We retrospectively analyzed 475 patients who underwent emergency appendectomies between January 2018 and February 2023 in a general hospital in Brazil. The patients were divided into 2 groups: complicated (n = 254) and uncomplicated (n = 221). Hyponatremia was defined as serum sodium levels < 136 mEq/L. The primary outcome was to evaluate if hyponatremia is associated with complicated appendicitis. RESULTS: The patients had a median age of 22 years, and the median serum sodium level was 137 mEq/L in patients with complicated appendicitis and 139 mEq/L in uncomplicated appendicitis (P < 0.001). The analysis of the receiver operating characteristic curve used as the best cutoff value of serum sodium of 136 mEq/L with a sensitivity of 45.7%, specificity of 86.4%, positive predictive value of 79.5%, and negative predictive value of 58.1% for the diagnosis of complicated AA. Of the 254 patients with complicated appendicitis, 84 (33.1%) had serum sodium levels below 136 mEq/L, while only 12 (5.4%) patients with uncomplicated appendicitis had values ​​below this cutoff. Patients with hyponatremia were 5 times more likely to develop complicated appendicitis. (odds ratio: 5.35; 95% confidence interval: 3.39-8.45) CONCLUSIONS: Preoperative serum sodium levels are a useful tool for predicting the severity of acute appendicitis. Due to its low cost and wide availability, it has become an extremely relevant marker.

Acute appendicitis in children: is preoperative hyponatremia a predictive factor of perforation/gangrene? A prospective study.

PURPOSE: Distinguishing between perforated/gangrenous from uncomplicated appendicitis in children helps management. We evaluated hyponatremia as a new diagnostic marker for perforated/gangrenous appendicitis in children. METHODS: A prospective study including all children with acute appendicitis who underwent appendectomy at our institution from May 2021 to May 2023. Medical history and clinical criteria were analyzed. All blood samples were taken upon admission including serum inflammatory markers and electrolytes. Patients were divided into two groups (Group I: uncomplicated and Group II: perforated/gangrenous), and data between both groups were compared. RESULTS: The study included 153 patients [Group I: 111 (73%), Group II: 42 (27%)]. Mean serum sodium concentration in children with perforated/gangrenous appendicitis was significantly lower compared to children with uncomplicated appendicitis (131.8 mmol/L vs. 138.7 mmol/L; p < 0.001). The ROC curve of preoperative sodium level to differentiate between perforated/gangrenous and uncomplicated appendicitis revealed an AUC of 0.981. The cut-off-value of sodium level < 135 mmol/L identified perforated/gangrenous appendicitis with a sensitivity of 94% and a specificity of 91% (p < 0.001). Predictive factors of perforated/gangrenous appendicitis were: age less than 5 years (12% vs. 3%; p = 0.02), experiencing symptoms for more than 24 h (100% vs. 58%; p < 0.001), body temperature more than 38.5 °C (52% vs. 13%; p < 0.001), a serum sodium level less than 135 mmol/L (90% vs. 6%; p < 0.001), and a CRP serum level more than 50 mg/L (71% vs. 17%; p < 0.001). CONCLUSIONS: Hyponatremia, upon admission, is a novel, objective biochemical marker that can identify perforated/gangrenous appendicitis in children. We advocate that the assessment of serum sodium level should be added to the diagnostic algorithm in children with suspected acute appendicitis. Surgical intervention in patients with hyponatremia should not be delayed, and non-operative management should be avoided.

Neuromyelitis optica spectrum disorder with herpes simplex viral infection presenting with syndrome of inappropriate antidiuretic hormone: A case report.

RATIONALE: Neuromyelitis optica spectrum disorder (NMOSD) is a demyelinating disease that causes lesions in areas with abundant aquaporin-4 (AQP4) channels, including the hypothalamus. Hypothalamic lesions can disrupt antidiuretic hormone regulation, resulting in hyponatremia due to syndrome of inappropriate antidiuretic hormone (SIADH). Various factors can trigger NMOSD, including viral infections. We report the case of a young female patient who presented with hyponatremia due to SIADH and was found to have bilateral hypothalamic lesions along with positive serum herpes simplex virus immunoglobulin M. PATIENT CONCERNS: An 18-year old female patient presented with fever and nausea that had persisted for 5 days. Three days after hospitalization, the patient complained of blurred vision, hiccups, and excessive daytime sleepiness. DIAGNOSIS: The patient hyponatremia was attributed to SIADH. Magnetic resonance imaging revealed bilateral lesions in the hypothalamus, and serum laboratory tests were positive for herpes simplex virus immunoglobulin M. On the 15th day of admission, the anti-AQP4 antibody test result was positive, leading to the diagnosis of NMOSD. INTERVENTIONS: On the initial suspicion of herpes encephalitis, treatment with acyclovir was initiated. However, upon the confirmation of after anti-AQP4 antibody, the patient was additionally treated with a high-dose intravenous steroid for 5 days. OUTCOMES: The patient fever, nausea, visual disturbances, and other complaints improved within 1 week of initiating steroid treatment. LESSONS: In young patients presenting with hyponatremia and suspected SIADH accompanied by neurological abnormalities, it is crucial to differentiate central nervous system diseases, including NMOSD, which can involve lesions in AQP4-abundant areas, such as the hypothalamus.

Predictors of in-hospital appendiceal perforation in patients with non- perforated acute appendicitis with appendicolithiasis at presentation.

INTRODUCTION: Appendicolithiasis is a risk factor for perforated acute appendicitis. There is limited inpatient data on predictors of progression in appendicolithiasis-associated non-perforated acute appendicitis. METHODS: We identified adults presenting with appendicolithiasis-associated non-perforated acute appendicitis (on computed tomography) who underwent appendectomy. Logistic regression was used to investigate predictors of in-hospital perforation (on histopathology). RESULTS: 296 patients with appendicolithiasis-associated non-perforated acute appendicitis were identified; 48 (16.2%) had perforation on histopathology. Mean (standard deviation [SD]) age was 39 (14.9) years. The mean (SD) length of stay (LOS) was 1.5 (1.8) days. LOS was significantly longer with perforated (mean [SD]: 3.0 [3.1] days) vs. non-perforated (mean [SD]: 1.2 [1.2] days) appendicitis (p < 0.001). On multivariate analysis, in-hospital perforation was associated with age > 65 years (OR 5.4, 95% CI: 1.4- 22.2; p = 0.015), BMI > 30 kg/m2 (OR 3.5, 95% CI: 1.3-8.9; p = 0.011), hyponatremia (OR 3.6, 95% CI: 1.3-9.8; p = 0.012). There was no significant association with age 25-65 years, gender, race, steroids, time-to- surgery, neutrophil percentage, or leukocyte count. CONCLUSION: Geriatric age, obesity, and hyponatremia are associated with progression to perforation in appendicolithiasis-associated non-perforated acute appendicitis.