36. All headaches are not GCA

Abstract

Introduction: Vasculitis is a heterogeneous groupof autoimmune disorders having multisystem involvement. In many cases, the neurological disorders have an atypical clinical course or even an early onset, and the healthcareprofessionalsshouldbeawareofthem. Case description: We report a case of 57-year-old Asian male without any significant past medical history admitted under the urology department. He had presented with abdominal pain and fever and was being treatedforpresumptivepyelonephritis (onantibiotics).Hewasreferred to rheumatology when he developed severe unilateral headache on right side with significant scalp tenderness. Headache involved temporal and fronto-parietal-occipital area with no jaw claudication or any significant visual disturbance. Therewasnolimb claudication orpolymyalgiasymptoms. On examination he had new onset hypertension (BP:174/94mmHg), rest of the systemic examination was normal with no bruit. Musculoskeletalandskinexaminationwasnormal. Investigations included CRP of 204, hemoglobin 133, white cell count 15.2(neutrophils:12.06),creatinine118(eGFR59).Liverfunction:normal. Urine dip: Normal and blood/urine culture: Negative. Immunological profile and viral screen was negative. Urgent CT head was done for severe headachewhichwasnormal. Patient was referred to rheumatology with provisional diagnosis of giant cell arteritisduetoheadacheandraisedinflammatorymarkers.Onreviewing his CT abdomen, the renal parenchyma showed symmetrical well demarcated bilateral involvement whichwas more in favor of renal infarct rather than pyelonephritis. CT angiography of abdomen was requested whichshowedmultiplevessel involvement includingmesentericarteryand bilateral renalarterieswithbeadedappearanceandstenosis. MRangiogram showed6mmaneurysm of PICA with stenosis of P1 segment of PCA. Currently he is being screened forADA2 deficiency. During his stay his renal function deteriorated, not responding previously to antibiotics. He was started on methylprednisolone pulse and antibiotics stopped in view ofworsening liver function.Onday3of methylprednisolonepulsehe had significant improvement of his headache with stabilization of renal andliver function.Ourplanistostarthimonsteroidsparingtherapybased ontheADA2levels. Discussion: The classification of vasculitis is still unsatisfactory as the patho-genetic mechanisms have not been fully understood. Existing criteria classify based on predominant vessel involvement but there is still some overlap between them. The prevalence of CNS involvement in mediumvessel vasculitisrangesaswidelyas2-10%anddoesnotusually occur until late in the course of the disease.Themostcommonly reported CNS manifestation is diffuse encephalopathy, followed in frequency by focal deficitsandseizures. Intracranialaneurysmsarerarewitharound15 reported cases usually multiple andlocated in supra- A s well as infra-tentorial compartments. Most of the cases presented with subarachnoid or parenchymal hemorrhage. Treatment guidelines are still not clear and most are treated conservatively by medical management. Repeat hemorrhages or re-bleed in spite of medical treatment have also been reported Deficiency of ADA2 (DADA2) has been recently recognized first molecularly described monogenic vasculitis havingbiallelic hypomorphic mutation in ADA2 gene. CNS involvement is one of the main features of DADA2 which presents with a wide spectrum of clinical manifestations ranging from systemic inflammation to cutaneous or visceral PAN like vasculopathyandearlyonset stroke. Our patient had presented with primary CNS and renal involvement with impending rupture aneurysm. Timely control of inflammation is pertinent in such cases with remission induction and maintenance to prevent stroke. Although cyclophosphamide is still used in such cases DADA2 usually require anti-TNF therapy. Our patient had good response to primarysteroidtherapy. Key learning points: Acute GCA-like neurological presentation of medium vessel vasculitis with cerebral involvement is rare. If not recognised inatimely fashion, itcanleadtosub-arachnoidhaemorrhagewhich isthemostcommonpresentationofsuchcases. DADA2 is a recently recognised entity that presents with stroke and vasculitis/vasculopathyandrespondstoanti-TNFtherapy. Conflicts of interest: The authors have declared no conflicts of interest.