The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is frequent in lung cancer patients. Here, we report a case with persistent hyponatremia, which suggested malignant SIADH and facilitated an early diagnosis of small cell lung cancer (SCLC). A combined radio-chemotherapy led to a partial remission and resolution of SIADH. An early relapse was indicated by reoccurring severe hyponatremia and increased copeptin levels, which were used as surrogate markers for the antidiuretic hormone (ADH). As palliative immunochemotherapy, together with fluid restriction and solute substitution, were unable to control hyponatremia, treatment with the ADH V2-receptor antagonist tolvaptan was initiated. Over time, the dose of tolvaptan needed to be increased, paralleled by a well-documented exponential increase of copeptin levels. In summary and conclusion, this is a rare case of a secondary failure to tolvaptan with unique documentary evidence of increasing copeptin levels. This observation supports the hypothesis that exceedingly high ADH levels may lead to competitive displacement of tolvaptan from the V2 receptor.

To optimize clinical care, it is imperative for providers to recognize their own inherent cognitive biases and the impact that has on their clinical decision making, thereby minimizing complications such as prolonged hospitalization, unnecessary healthcare spending, and impaired patient satisfaction and functional outcomes.

BACKGROUND: Vortioxetine, known for its efficacy in treating depression through its effects on various neurotransmitters, has not been previously reported to induce syndrome of inappropriate secretion of antidiuretic hormone (SIADH).
METHODS: This case report describes a 74-year-old man with major depressive disorder who developed SIADH 1 week after starting treatment with vortioxetine. SIADH is characterized by symptoms such as headache, nausea, disorientation, and seizures, stemming from hyponatremia (123 mEq/L), without dehydration or edema. Vortioxetine was discontinued, and an alternative drug, mianserin, was initiated. The patient was restricted from drinking water due to hyponatremia. The serum Na concentration improved over time to within the normal range by the second week after admission.
CONCLUSIONS: This is the first case report of vortioxetine-induced SIADH.

Tuberculous meningitis (TBM) is a severe form of extrapulmonary tuberculosis (TB) characterized by the invasion of Mycobacterium tuberculosis into the meninges surrounding the brain and spinal cord. It triggers an intense inflammatory response, leading to neurological complications if not promptly and adequately managed. TBM often precipitates muscle weakness, neurological deficits, respiratory challenges, swallowing difficulties, joint contractures, and pain. Physiotherapy intervention is essential in treating these problems by personalized treatment strategies and treatment plans to enhance muscle strength, motor control, coordination, and overall mobility. This case report aims to highlight the significant role of physiotherapy in improving the quality of life (QOL) and functional abilities of patients with TBM. The current case report reviews the case of a 73-year-old male who presented with complaints of generalized weakness and difficulty in swallowing. The patient had a history of fever for the last six months. Magnetic resonance imaging (MRI) and high-resolution computed tomography (HRCT) diagnosed the case as TBM with miliary TB. Six weeks of targeted intensive rehabilitation program was designed according to the patient\'s impairments initiated from the intensive care unit (ICU) phase. The main goals of physiotherapy were to start early bed mobility, maintain joint integrity, improve postural strength and swallowing, and make the patient independent in transfer and activities of daily living (ADLs). After a six-week intensive physiotherapy (TIP-6) program, the patient exhibited significant improvements in muscle strength and independence in ADLs. This case highlights the critical role of physiotherapy in enhancing the QOL and functional abilities of patients with severe TB-related conditions.

Autoimmune polyglandular syndrome II (APS-II), also known as Schmidt syndrome, is a rare endocrine disorder characterized by endocrine and non-endocrine illnesses. Addison\'s disease and at least one additional autoimmune condition, such as autoimmune thyroid disease or type 1 diabetes mellitus (T1DM), are features of APS-II. It can result from genetic and non-genetic factors. We present a case of a 60-year-old female patient with a history of T1DM and a recent diagnosis of Hashimoto\'s thyroiditis who was admitted to the nephrology department for hyponatremia. Investigations showed the presence of adrenal insufficiency (AI), so she was diagnosed with APS-II and had the full triad of this syndrome. Thus, it is important to think about the diagnosis of AI or other autoimmune conditions in a patient who already has one or more autoimmune diseases.

The CDK4/6 inhibitor, abemaciclib, is now the standard of care adjuvant therapy for patients with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) tumors at high risk of recurrence. Real-world usage uncovers emerging side effects that may have been previously unreported in clinical trials. Here, we present the clinical course of a patient who developed a syndrome of inappropriate antidiuretic hormone (SIADH) without underlying kidney injury due to abemaciclib use.

UNASSIGNED: Neuromyelitis optica spectrum disorders (NMOSD) is often misdiagnosed or delayed because of the complex and diverse clinical manifestations, especially the atypical initial presentation. Hyponatremia can be an infrequently isolated initial presentation of NMOSD and is associated with hypothalamus involvement. Awareness of this mechanism will help clinicians to identify NMOSD early, treat it in time and improve the prognosis.
UNASSIGNED: We describe a 36-year-old woman who developed repeated hyponatremia and then experienced diplopia. Serum AQP4, MOG, MBP and GFAP antibody were detected, and NMOSD was finally diagnosed.
UNASSIGNED: She responded well to high-dose glucocorticoids. Sequential treatment with mycophenolate mofetil (MMF) was prescribed. Two-month follow-up revealed full recovery. So far, after 10 months, the patient still has no recurrence.
UNASSIGNED: For young patients, repeated hyponatremia, with or without slight fever, and no evidence of obvious infection, brain magnetic resonance imaging (MRI) and serum AQP4/MOG antibody detection may be useful to determine whether there is a possibility of NMOSD.

Ectopic olfactory neuroblastoma (ONB) is a rare neuroendocrine sinonasal malignancy which arises from sinonasal regions where olfactory neuroepithelium does not exist. Presentation of syndrome of inappropriate antidiuretic hormone release (SIADH) in patients with ectopic ONB is extremely rare. We report a case of a 22-year-old patient with ectopic ONB and paraneoplastic SIADH that was managed at our center. The ONB was arising from the left lamina papyracea and extending into the maxillary and ethmoid sinuses and filling the nasal cavity. Correction of sodium levels occurred within 24 hours of endoscopic resection via a combined trans-nasal transorbital approach. To avoid negative sequela secondary to rapid sodium correction, the patient was managed by desmopressin to obtain gradual sodium correction, which was achieved on the fourth postoperative day. Ectopic presentation of ONB with paraneoplastic SIADH is extremely rare with only 7 cases reported in the literature to date. Management via surgical resection and/or radiotherapy for these patients requires the managing clinician to be vigilant of serum sodium levels. A multidisciplinary approach is essential for optimal outcomes.

Nirmatrelvir-ritonavir (Paxlovid) is a brand-new oral antiviral medication for treating mild to severe COVID-19. The Food and Drug Administration (FDA) issued an Emergency Use Authorization (EUA) for ritonavir-nirmatrelvir on December 22, 2021, to treat COVID-19. We describe a case of mild COVID-19 infection who developed severe hyponatremia following the administration of Paxlovid. Clinical and laboratory evaluations suggest SIADH, likely secondary to Paxlovid. The potential side effects of this medication still require further study.

Malignant syndrome (MS) in Parkinson\'s disease (PD) is a rare complication that occurs in patients who have a history of PD and are taking dopaminergic drugs. The syndrome is quite similar to neuroleptic malignant syndrome (NMS) in presentation and is a potentially fatal syndrome. Awareness of symptoms, early diagnosis, and the ability to differentiate it from NMS is important to prevent mortality. Clinical manifestations of MS are similar to NMS and include altered mentation, rigidity, fever, leukocytosis, and elevated serum creatine kinase (CK). However, MS is differentiated from NMS by the precipitating factors; of which, the commonest precipitating factor for MS is dopaminergic drug withdrawal or dose reduction while other less common causes include infection, dehydration, and hot weather. We present a rare case of MS in a patient with a history of PD precipitated by severe dehydration and hot weather in the absence of dopaminergic drug withdrawal. He presented with fever, severe rigidity, altered mentation, dehydration, leukocytosis, and elevated CK. He was correctly diagnosed with MS and promptly treated, preventing mortality. The triad of fever, severe rigidity, and altered sensorium in a patient with a history of PD should prompt evaluation for MS in addition to NMS to initiate appropriate treatment and prevent mortality.