When hypertensive encephalopathy is present, headache is coded as 10.3.3 Headache attributed to hypertensive encephalopathy. When the diagnosis of phaeochromocytoma has not yet been made, and hypertensive encephalopathy is not present, patients may meet the diagnostic criteria for 10.3.2 Headache attributed to hypertensive crisis without hypertensive encephalopathy.
Headache attacks, usually severe and of short duration (less than 1 hour), accompanied by sweating, palpitations, pallor and/or anxiety, caused by phaeochromocytoma.
A. Recurrent discrete short-lasting headache episodes fulfilling criterion C
B. Phaeochromocytoma has been demonstrated
C. Evidence of causation demonstrated by at least two of the following:
1. headache episodes have commenced in temporal relation to development of the phaeochromocytoma, or led to its discovery
2. either or both of the following:
a) individual headache episodes develop in temporal relation to abrupt rises in blood pressure
b) individual headache episodes remit in temporal relation to normalization of blood pressure
3. headache is accompanied by at least one of the following:
4. headache episodes remit entirely after removal of the phaeochromocytoma
D. Not better accounted for by another ICHD-3 diagnosis.
10.3.1 Headache attributed to phaeochromocytoma occurs as a paroxysmal headache in 51-80% of patients with phaeochromocytoma. It is often severe, frontal or occipital and usually described as either pulsating or constant in quality. An important feature of the headache is its short duration: less than 15 minutes in 50% and less than 1 hour in 70% of patients. Associated features include apprehension and/or anxiety, often with a sense of impending death, tremor, visual disturbances, abdominal or chest pain, nausea, vomiting and occasionally paraesthesia. The face can blanch or flush during the attack.
The diagnosis of phaeochromocytoma is established by the demonstration of increased excretion of catecholamines or catecholamine metabolites, and can usually be secured by analysis of a single 24-hour urine sample collected when the patient is hypertensive or symptomatic.