Extensive Cerebral Venous Thrombosis as an Isolated Presentation in a COVID-19-Positive Young Adult

A male patient in his 30s, with no known comorbidities, arrived at the emergency department complaining of severe headache and subjective weakness in the left arm. The headache was described as severe, generalized, and throbbing. It persisted for four days and was initially only associated with vomiting. The patient also expressed a weakness in his left arm that started 24 hours before his presentation. COVID-19 PCR swab was done as a part of hospital policy for any patient who requires admission to the hospital and resulted positive. He had no recent COVID-19 test done.

On systemic review, the patient denied any symptoms commonly reported in patients with COVID-19; he had no history of fever, coughing, chest pain, or difficulty in breathing. There were no reports of a witnessed seizure, loss of consciousness, or abnormal behavior. The patient had no diarrhea, abdominal pain, or burning micturition. He had no rash as well. He had no recent history of trauma. The patient reported that he neither drank alcohol nor smoked any sort of tobacco. The patient had no known family history of any blood disorders, strokes, or similar presentations. He had no recent travel history and no recent contact with any COVID-19-positive patient. He lived with a roommate, who was healthy and had no recent upper respiratory tract infection. The patient was unvaccinated, as the vaccination campaign was not yet started. 

On examination, his vital signs were stable. His blood pressure was 128/84 mmHg, pulse 100 beats per minute, respiratory rate 18 breaths per minute, oxygen saturation (SpO2) 100% on room air, and a temperature of 36.3 °C. On general examination, the patient had jerky movements in the left arm, but he was conscious and oriented with a Glasgow coma scale (GCS) of 15/15. He had no neck stiffness. The cranial nerve examination was normal. In the motor examination, his power in bilateral upper limbs and lower limbs was normal scoring 5/5 as there was an active movement of all limbs against gravity with full resistance. The cerebellar examination was normal. 

After the initial examination, considering the clinical presentation of the patient, he was sent for a brain CT scan; however, on the way to the radiology suite, he developed a tonic-clonic seizure. The emergency team intervened with 10 mg of diazepam. Nevertheless, the patient soon had recurrent episodes of seizure within 30 minutes and received 10 mg of diazepam; he was also loaded with 1 gram of levetiracetam, which aborted the seizures. The patient had a normal glucose level, with no hypoglycemia. Soon after, the patient had a third attack of seizure. The patient did not regain consciousness, and he was not able to maintain his airway. The patient’s GCS dropped to 8/15 with eye-opening 2/4, verbal response 2/5, and motor response 4/6. As a result, the emergency team decided to intubate him with rapid sequence intubation. Medications used for intubation were midazolam 20 mg as a pretreatment medication, propofol 100 mg and fentanyl 100 microgram were used for induction, and suxamethonium chloride 100 mg as a neuromuscular blocking agent. The readings of venous blood gas post-intubation is shown in Table 1:

1: Venous blood gas post-intubation

PCO2: partial pressure of carbon dioxide; HCO3: bicarbonate

A chest x-ray was done and reported normal with an endotracheal tube in place. The CT brain and venogram scans were done after the patient was stabilized. The CT brain scan showed hyperdense superior sagittal sinus as shown in Figure 1, and superficial cortical veins bilaterally, which strongly suggested that the patient was having thrombosis. 

CT venogram done showed extensive thrombosis of the superior sagittal sinus and the superficial cortical veins bilaterally as shown in Figure 2 and Figure 3.

Apart from brain imaging, the initial blood investigations were performed on the same day of the patient presentation and are given in Table 2.

2: Initial blood investigations results

APTT: activated partial thromboplastin clotting time; INR: (international normalized ratio; LDH: lactate dehydrogenase

Initially, differentials to the patient’s clinical presentation were limited to investigating the presenting focal seizures; a history of alcohol consumption was ruled out, and a plan to rule out traumatic cerebral injury, hypoperfusion, or hemorrhage was made. Parasitic infections such as neurocysticercosis or malaria may also present similarly, but those were also ruled out by a CT brain. Brain imaging revealed evidence of CVT. With the current reality of the COVID-19 pandemic, it was critical to consider this virus as a cause of the patient’s hypercoagulable state and thrombosis. 

Further investigations were done as an inpatient to rule out other diseases. Differential diagnoses that were sought included relevant clotting factor disorders such as protein C and S deficiencies, thrombophilia, including mutations in Factors II and Factor V Leiden and labs reported negative. A lupus anticoagulant profile was done including anticardiolipin IgM/IgG and antinuclear antibodies (ANA), which were reported negative. An extractable nuclear antigen (ENA) panel was done to rule out autoimmune diseases and resulted negative. A thyroid function test was done and the results were within normal ranges. Urine culture, blood culture, and respiratory culture were all performed on admission, and the final result showed no growth.

In relation to the management, in the emergency department, the patient received diazepam and levetiracetam after developing multiple seizure attacks. Moreover, he was intubated and sedated because of the low GCS and unsecured airway. As meningitis was one of the differentials, ceftriaxone, acyclovir, and dexamethasone were administered.

The patient was admitted to the ICU. He was intubated and sedated. The patient was continuously monitored with frequent arterial blood gas tests and had an arterial line placed for blood pressure monitoring. On day three of admission, the patient had no seizures and was planned to wean off sedation. After the patient was extubated, he was shifted to a regular isolation ward. A follow-up CT brain was done after 10 days of admission and it was seen that the previously thrombosed cerebral venous sinuses and cortical veins were now less hyperdense, suggesting recanalization, which is a favorable regressive course. There was resolution of the hyperdensity in the superior sagittal sinus (no delta sign) on the plain CT brain as shown in Figure 4.

Throughout the admission, he was kept on enoxaparin injections and then started on warfarin. The patient’s (international normalized ratio (INR) was checked daily until a target INR of 2.93 was reached. The patient was not started on any medication for the COVID-19 virus and was given supportive care. As per the hospital protocol, the patient was kept in isolation and shifted out of isolation after completing 14 days of isolation and receiving two negative COVID-19 swab tests. He remained asymptomatic throughout the admission and did not suffer from any further neurologic deficits. He was discharged home on warfarin 6 mg once per day and levetiracetam 1500 mg twice per day. Also, he was given a follow-up appointment with the neurology clinic. Despite the scheduled follow-up appointment, the patient preferred to go back to his home country and follow up.