Comparison of CT and MR features with clinical outcome in patients with Rocky Mountain spotted fever.
OBJECTIVE
To compare neuroimaging findings and clinical features in patients with Rocky Mountain spotted fever and to determine the impact of imaging studies in the treatment of these patients.


METHODS
We reviewed the brain CT scans (n = 44), MR images (n = 6), or both (n = 4), and one MR spinal study in 34 patients with Rocky Mountain spotted fever, proved by definitive serologic criteria. Records were reviewed with attention to clinical symptoms and therapeutic modifications based on neuroimaging; outcomes were compared with imaging findings.


RESULTS
Abnormalities, consisting of infarctions, cerebral edema, meningeal enhancement, and prominent perivascular spaces, were found on four of 44 CT scans and on four of six MR studies. The spinal MR study showed abnormal enhancement of the lower spinal cord and cauda equina. Nonspecific clinical symptoms were present in all patients in whom neuroimaging findings were abnormal and in 80% of patients whose CT and/or MR findings were normal. After treatment, return to baseline clinical status was documented in 67% of patients with abnormal imaging findings and in 93% with normal findings. Death occurred in 17% of patients with abnormal neuroimaging results and in none of those with normal results.


CONCLUSIONS
Abnormalities on neuroimaging studies were not common in patients with Rocky Mountain spotted fever. When present, they were subtle. Symptoms at presentation and unfavorable outcomes were more prevalent when CT or MR findings were abnormal. Abnormalities identified on neuroimaging studies did not alter clinical treatment in any patient.
Bonawitz
C
C
Department of Radiology, University of North Carolina School of Medicine, Chapel Hill 27599, USA.
Castillo
M
M
Mukherji
S K
SK
D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001921:Brain / Q000473:pathology; D001925:Brain Damage, Chronic / Q000175:diagnosis; D001929:Brain Edema / Q000175:diagnosis / Q000473:pathology; D002420:Cauda Equina / Q000473:pathology; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000188:drug therapy; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002542:Intracranial Embolism and Thrombosis / Q000175:diagnosis* / Q000188:drug therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D008590:Meningoencephalitis / Q000175:diagnosis* / Q000188:drug therapy; D008875:Middle Aged; D009460:Neurologic Examination; D012189:Retrospective Studies; D012373:Rocky Mountain Spotted Fever / Q000175:diagnosis* / Q000188:drug therapy; D013116:Spinal Cord / Q000473:pathology; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents