This patient presents with a constellation of renal and extrarenal medical issues including hypertension, recurrent urinary tract infections, mitral valve prolapse, and diverticulosis, which suggests a diagnosis of autosomal dominant polycystic kidney disease (ADPKD). The cause of his severe headache is, therefore, most likely a subarachnoid hemorrhage (SAH) secondary to a ruptured berry aneurysm, which is another extrarenal manifestation of ADPKD.
Any headache that is sudden and severe should raise concern for SAH. Common descriptors of SAH include "worst headache of life" or "thunderclap headache." Additional symptoms are nuchal rigidity and photophobia which result from blood irritating the meninges (meningismus). Most SAHs occur in patients between 40 and 60 years of age. Noncontrast head CT should be done if SAH is suspected. If there is a strong clinical suspicion and head CT is negative, lumbar puncture should be performed (which could reveal yellow CSF, known as xanthochromia, if positive).
Dachs et al. discuss the diagnosis of SAH using CT scan. Most SAHs are caused by a rupture of a berry (saccular) aneurysm, usually in the anterior circulation on the Circle of Willis at junctures or bifurcations (e.g. at the junction of the anterior communicating artery with the anterior cerebral artery). Other causes of SAH include arteriovenous malformations (AVMs), trauma, intracranial arterial dissections, amyloid angiopathy, bleeding diatheses, and illicit drug use (particularly cocaine and amphetamines).
Vlak et al. discuss the prevalence of intracranial aneurysm formation. Chronic hypertension is a risk factor for intracranial aneurysm formation, and ADPKD specifically is associated with nearly 7x higher risk of intracranial aneurysm. Other genetic conditions associated with intracranial aneurysms are connective tissue diseases such as Ehlers-Danlos syndrome and pseudoxanthoma (but NOT Marfan's). Other risk factors for aneurysm formation include cigarette smoking, estrogen deficiency, and coarctation of the aorta.
Image A shows a CT scan showing a SAH.
Image B shows the Circle of Willis with the most common locations for ruptured aneurysms circled.
1: Migraines generally begin with moderate pain and increase to a maximal level over 1-2 hours in a crescendo pattern and should not be associated with meningismus.
2: Brain tumors are not associated with sudden headaches usually (typically develop over months). Nausea, vomiting, worsening of headache with postural changes, and focal neurologic deficits are common findings.
3: Headache with jaw claudication, visual disturbances, or polymyalgia rheumatica would be more suggestive of temporal arteritis as a cause of headache.
5: Carotid dissection can be associated with rapid onset of headache, but this is usually in the setting of strenuous exercise or a situation where neck trauma has occurred.
Conway JE, Hutchins GM, Tamargo RJ. Marfan syndrome is not associated with intracranial aneurysms. Stroke. 1999 Aug;30(8):1632-6. PMID: 10436113
PMID:10436113 (Link to Abstract)
Vlak MH, Algra A, Brandenburg R, Rinkel GJ. Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol. 2011;10(7):626. PMID: 21641282
PMID:21641282 (Link to Abstract)
Dachs R, Graber MA, Darby-Stewart A. Subarachnoid hemorrhage and the CT Scan. Am Fam Physician. 2011 Sep 15;84(6):632-6.
PMID:21916387 (Link to Abstract)
USMLE World Step 1 QBank Question #497. Copyright © USMLEWorld, LLC 2012