Mikhaiel John P, Parasram Melvin, Park Jaehan, Cappucci Stefanie, McGuone Declan, Falcone Guido J, Sheth Kevin N, Gilmore Emily J
Departments of Neurology.
Pathology, Yale School of Medicine, New Haven, CT.
Neurologist. 2025 Jan 1;30(1):34-38. doi: 10.1097/NRL.0000000000000586.
Rocky Mountain Spotted Fever (RMSF) is a tick-borne disease caused by Rickettsia rickettsii ( R. rickettsii ). RMSF presents after a tick bite with fever, rash, and headache but can also cause more serious neurological manifestations. We report a case of RMSF encephalitis presenting with altered sensorium and rapid progression to coma, fever, and petechial rash, and an magnetic resonance imaging (MRI) brain notable for a "starry sky" pattern.
A 61-year-old woman presented with confusion and fever and was diagnosed with a urinary tract infection. Two days later, she became comatose. MRI brain revealed lacunar infarcts in the right centrum semiovale and splenium of the corpus callosum. Lumbar puncture was notable for neutrophilic pleocytosis and elevated protein with negative bacterial and viral cultures. Empiric meningitis therapy was initiated, and she was transferred to our institution. On transfer, she was febrile, comatose, and had a diffuse petechial rash. Repeat MRI brain demonstrated diffuse, innumerable punctate foci of diffusion restriction with susceptibility-weighted signal attenuation throughout cerebral hemispheres in a "starry sky" pattern. Skin biopsy revealed perivascular lymphocytic infiltrates. Serologic RSMF antibody titers were obtained, and doxycycline was initiated for presumed RMSF encephalitis. The family opted to pursue palliative measures, given no clinical improvement. RSMF titers and postmortem PCR from brain tissue were positive for R. rickettsii.
This case report highlights the clinical presentation of RMSF encephalitis. RMSF encephalitis should be suspected in a patient presenting with encephalopathy, fever, petechial rash, and MRI brain findings of diffuse punctate foci of diffusion restriction and susceptibility-weighted signal attenuation in a "starry-sky" pattern.
落基山斑疹热（RMSF）是一种由立氏立克次体（R. rickettsii）引起的蜱传疾病。RMSF在蜱叮咬后出现发热、皮疹和头痛，但也可引起更严重的神经表现。我们报告一例RMSF脑炎病例，表现为意识改变并迅速进展为昏迷、发热和瘀点皮疹，脑部磁共振成像（MRI）显示为“星空”样表现。
一名61岁女性因意识模糊和发热就诊，被诊断为尿路感染。两天后，她陷入昏迷。脑部MRI显示右侧半卵圆中心和胼胝体压部有腔隙性梗死。腰椎穿刺显示中性粒细胞增多和蛋白升高，细菌和病毒培养均为阴性。开始经验性脑膜炎治疗，随后她被转至我院。转院时，她发热、昏迷，并有弥漫性瘀点皮疹。复查脑部MRI显示弥漫性、无数点状扩散受限病灶，在整个脑半球的磁敏感加权成像上呈“星空”样信号衰减。皮肤活检显示血管周围淋巴细胞浸润。检测了血清学RSMF抗体滴度，并开始使用强力霉素治疗疑似RMSF脑炎。由于临床无改善，家属选择采取姑息措施。脑组织的RSMF滴度和死后PCR检测显示立氏立克次体呈阳性。
本病例报告突出了RMSF脑炎的临床表现。对于出现脑病、发热、瘀点皮疹且脑部MRI表现为弥漫性点状扩散受限病灶和磁敏感加权信号衰减呈“星空”样的患者，应怀疑RMSF脑炎。
