Abstract
Introduction:
Severe headaches with nonspecific characteristics raise concern for idiopathic intracranial hypertension (IIH) in a young adult female patient. Clinical features of severe headache, vision loss, and papilledema; normal neuroimaging and elevated opening pressure on lumbar puncture are diagnostic of IIH or pseudotumor cerebri. Etiology is often attributed to obesity in young female patients. We present a rare case of Pseudotumor cerebri in a non-obese female patient with severe hypocalcemia.
Case:
A 26 year old Hispanic female patient with past medical history of hypocalcemia, but off her medications, presented to ER for worsening headache for over a month. Without any specific triggers, she began having headaches in her bitemporal region. The pain was continuous, pressure-type, and 9/10 intensity at its worst. It was associated with nausea and blurring of vision and was refractory to ibuprofen. Patient endorsed severe muscle cramps on review of systems. Physical examination demonstrated mild distress due to the headache, positive Trousseau’s sign, and bilateral papilledema. Laboratory studies revealed serum total calcium level of 4.8 mg/dL, albumin 3.5 g/dL, ionized calcium 0.71 mmol/L, serum phosphate 5.3 mg/dL, intact PTH 300.1 pg/mL, 25-OH Vitamin D 14.3 ng/mL and 1, 25-Dihydoxy Vitamin D 14.1 pg/mL, alkaline phosphatase 131 IU/L, 24-hour urinary calcium 48mg/d and 24 hour urinary calcium/creatinine ratio 50 mg/g. Her MRI brain and MR venogram were unremarkable. Lumbar puncture had elevated opening pressure of 46 cm of H2O. The patient was started on Acetazolamide, oral calcium, and calcitriol without resolution of headaches and hypocalcemia. Acetazolamide was discontinued when she developed severe hypokalemia. With diagnosis of pseudohypoparathyroidism, the dose of elemental calcium was doubled and calcitriol dose increased to 1 mcg BID with improvement of serum calcium, symptoms, and papilledema.
Discussion:
While IIH could be associated with certain medications and systemic conditions, obesity or recent weight gain are the most commonly cited causes of IIH. Severe hypocalcemia is a rare and less known etiology of IIH. Cases of adult patients are reported with a variety of etiologies of severe hypocalcemia. Severe hypocalcemia leading to hypersecretion of cerebrospinal fluid is postulated as a possible mechanism but evidence is lacking in literature. Chronic, rather than acute, severe hypocalcemia is likely to precipitate IIH. Visual symptoms, headache and papilledema are difficult to resolve with conventional medical therapy without correction of underlying severe hypocalcemia. We conclude that before considering surgical interventions for cases which are refractory to medical therapy, rare underlying conditions like severe hypocalcemia must be investigated and treated optimally.
Management of Cerebellar Tonsillar Herniation following Lumbar Puncture in Idiopathic Intracranial Hypertension