Atypical Presentation of Disseminated Tuberculosis With Third Cranial Nerve Palsy and Aortic Aneurysm: A Case Report

Tuberculosis (TB) remains a leading cause of mortality among infectious diseases globally, posing significant diagnostic and therapeutic challenges despite being curable.This case highlights a delayed diagnosis of miliary TB with rare and severe complications in a patient with an atypical presentation. A 44-year-old female of African origin presented with non-specific symptoms, including fever, malaise, and deranged liver function tests, after travel to Nairobi. After nearly two months of intermittent symptoms, she developed neurological signs, including a third cranial nerve palsy, eye pain, and ptosis, prompting further investigation. Brain imaging revealed multiple enhancing nodules consistent with TB granulomas and a striato-capsular infarct. Subsequently, thoracic imaging showed a thoracic aortic aneurysm, extensive lung miliary nodularity, and "tree-in-bud" appearance, indicative of miliary tuberculosis. The patient developed tuberculous vasculopathy, likely contributing to the acute brain infarct, and a rare but life-threatening tuberculous aortic aneurysm. While cranial nerve palsies are known complications of central nervous system TB, isolated third nerve involvement and the co-occurrence of a large-vessel aneurysm are uncommon. This case emphasizes the need for a high index of suspicion for TB in patients with unusual or multifocal symptoms, even in the absence of typical signs. Early diagnosis, followed by prompt initiation of antituberculosis therapy with appropriate surgical intervention for complications such as aneurysms, is important in reducing morbidity and preventing fatalities in such complex presentations.