Saudi Critical Care Journal

: 2021  |  Volume : 5  |  Issue : 3  |  Page : 50--52

An unusual case report of COVID-19 presenting with syndrome of inappropriate ADH secretion

Wasim Shabbir Shaikh1, Ayesha Shaikh2, K Bhosle Sachin3, Zeyad A L Rais3, Hesham El Kholy3,  
1 Rashid Hospital, Dubai, UAE
2 Department of Ophthalmology, Medeor Hospital, Dubai, UAE
3 Medical ICU, Rashid Hospital, Dubai, UAE

Correspondence Address:
Wasim Shabbir Shaikh
Rashid Hospital, Dubai


Coronavirus disease-2019 (COVID-19) caused by novel coronavirus continues to produce enormous health effects and deaths since it started in 2019. Research till now has shown that COVID-19 manifests with unusual presentations causing various challenges in its management. Hyponatremia is a common condition found in critical care units and syndrome of inappropriate ADH (SIADH) accounts for one-third of those cases. Several infections associated with COVID-19 have been reported, but there are only few case reports of association with SIADH. We report the case of a 30-year-old male admitted with seizure due to acute symptomatic hyponatremia and SIADH attributed to COVID-19.

How to cite this article:
Shaikh WS, Shaikh A, Sachin K B, L Rais ZA, El Kholy H. An unusual case report of COVID-19 presenting with syndrome of inappropriate ADH secretion.Saudi Crit Care J 2021;5:50-52

How to cite this URL:
Shaikh WS, Shaikh A, Sachin K B, L Rais ZA, El Kholy H. An unusual case report of COVID-19 presenting with syndrome of inappropriate ADH secretion. Saudi Crit Care J [serial online] 2021 [cited 2021 Dec 3 ];5:50-52
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Full Text


Syndrome of inappropriate ADH (SIADH) is one of the causes of hyponatremia in critical care units worldwide. Various etiologies associated with hyponatremia pose significant challenges in treating this disorder. SIADH occurs in response to inappropriate release of antidiuretic hormone in spite of low serum osmolarity. COVID-19 generally presents as an upper or lower respiratory system illness in the majority of patients, but there are a few reports of COVID-19 presenting as a neurological emergency. We describe the case of a young man admitted with seizure due to acute symptomatic hyponatremia and SIADH attributed to COVID-19.

 Case Report

A 30-year-old premorbidly healthy male, a salesman by profession, was brought to hospital by relatives in an unconscious state following episode of fall and seizure. On arrival to emergency he was febrile, tachycardic, normotensive, Glasgow Coma Scale 3, and pupils reactive with oxygen saturation 97% on room air. There were no complaints of diarrhea, vomiting, chest pain, rhinorrhea, headache, blurring of vision, anosmia, dehydration or any history of bronchial asthma, chronic obstructive pulmonary disease, and heart failure and he was not on any medications. He was intubated and ventilated for airway protection. Another general examination was normal with bilateral basal coarse crepts on auscultation. Electrocardiogram was normal. Arterial blood gas analysis showed normal parameters except sodium 116 mEq/L which demonstrated profound hyponatremia. Urgent whole-body scan done for suspected polytrauma did not reveal any abnormality in the brain, chest, and abdomen. Emergency blood/serum investigations consisting hepatic, renal, cardiac profile sent on admission were normal except sodium 112 mEq/L [Table 1]. Chest X-ray [Figure 1] showed some pulmonary infiltration mostly in the periphery of both lungs. As per routine protocol during this pandemic, we did nasopharyngeal swab for COVID-19 which came positive. Lumbar puncture for cerebrospinal fluid examination was done as per the advice of neurologist in view of suspected meningitis, it did not show any abnormality. He was then transferred to dedicated COVID intensive care unit (ICU) for further management.{Table 1}{Figure 1}

He was started on treatment for COVID-19 as per the national guidelines. Hyponatremia after ICU admission was confirmed with low plasma osmolarity 239 mOSM/kgH20, normal urine osmolarity 234 mOSM/kgH20, with high urinary sodium 46 mEq/L in the absence of any hypovolemia. Hence, according to the time of onset and severity criteria of hyponatremia, the patient was diagnosed to have acute severe symptomatic hyponatremia with need of urgent correction. Our first priority was to reach safe sodium level of 120 mEq/L with maximum permissible sodium correction rate 8–12 mEq/day in 24 h. One hundred ml of 3% saline bolus was given over 20–30 min followed by titrated slow infusion 25 ml/h for 24 h as per sodium levels. Serum sodium was measured every 4–6 hourly and within 24 h the sodium concentration reached 120 mEq/L and normalized to 132 mEq/L over the next 3 days. COVID-19 management was continued with steroid, anticoagulation, and lung-protective ventilation. The patient was eventually extubated on the 4th day without any neurological deficit. He was discharged from the ICU on the 5th day and later followed up in the endocrinology department with normal electrolytes.


SIADH was first described by Bartter and Schwartz as the cause of euvolemic hyponatremia.[1]

Diagnostic criteria for SIADH comprise low plasma sodium concentration, low plasma osmolarity, urine osmolarity typically >100 mOsm/kg, urine sodium concentration >30 mmol/l, low-normal plasma urea, serum creatinine, uric acid, clinical euvolemia, absence of adrenal, thyroid, pituitary and renal insufficiency, no recent use of a diuretic, and appropriate clinical context.[2]

There are several well-documented causes of SIADH most common being head injury, brain tumors, central nervous system infections, postoperative procedures, and drugs such as anticonvulsants. It can also occur in extracranial tumors where ectopic production of ADH is high. Hyponatremia is frequently associated with community-acquired pneumonia and one of the underlying mechanisms is SIADH.[3] Hyponatremia was also found to be associated with higher risk of severe illness and increased in-hospital mortality in patients with COVID-19.[4],[5]

Our patient was euvolemic with normal thyroid, hepatic, renal, and lipid status so attempts were made to find out the primary etiology of hyponatremia. Neither biochemical investigation nor radiological imaging suggested any obvious cause of SIADH except coexisting COVID-19. Even though the cortisol levels were not checked patient did not have any symptoms suggestive of pituitary or adrenal insufficiency. Hence, in accordance to SIADH criteria, diagnosis of acute severe hyponatremia, secondary to SIADH attributed to COVID-19 pneumonia, was confirmed.

Proposed pathophysiology of hyponatremia in COVID-19 is multifactorial ranging from inadequate immune response causing kidney damage,[6] the presence of viral particles in the kidney,[7] and expression of angiotensin-converting enzymes which are also found in the heart, lung, and intestines.[8] Hyponatremia was found as an independent predictor of higher mortality in pneumonia indicating the need for early diagnosis and proper medical management of the patient.[9],[10]

Symptoms associated with hyponatremia encompass a broad spectrum of clinical presentation ranging from subtle cognitive deficiencies to life-threatening neurological disturbances as seen in our patient. Diagnosis of hyponatremia requires assessment of volume status of the patient along with ruling out other causes such as hypothyroidism and adrenal insufficiency which results in similar water and electrolyte disturbances. According to the existing data, the cause of hyponatremia in COVID-19 includes mainly SIADH and digestive losses of sodium through vomiting and diarrhea.[11]

There are currently no clinical guidelines for the management of hyponatremia in COVID-19. Therapeutic approach depends on etiology, volume status, and comorbidities of the patient. Hyponatremia secondary to SIADH mainly needs fluid restriction and sometimes hypertonic saline administration depending on neurological complication which was seen in our case. This approach is very important to avoid iatrogenic complications such as pulmonary edema and exacerbation of lung damage secondary to COVID-19.


Hyponatremia and its related neurological complications can be presenting symptoms of COVID-19 patients. The cause of hyponatremia in these patients is diverse. It is important to establish the exact etiology of hyponatremia because therapeutic management differs depending upon pathophysiology. SIADH should be considered as a differential diagnosis, as a possible cause of hyponatremia and treatment should be done without secondary damage to already susceptible lung parenchyma in patients presenting with COVID-19.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.


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