Neurological manifestations of Kyasanur Forest disease: a retrospective cohort study from South India.

BACKGROUND: Kyasanur Forest disease (KFD) is a viral zoonotic disease where patients present with febrile illness and haemorrhagic manifestations in the first phase. In a small fraction of patients, the fever may be biphasic. This study aimed to describe the neurological manifestations of patients with KFD in the first and second phases of the illness. METHODS: This is a retrospective cohort study of 297 patients admitted with a molecular diagnosis of KFD from December 2018 to December 2020. The case records of these patients were reviewed for evidence of neurological involvement. RESULTS: A total of 34 (11.5%) patients in the first phase and 16 (36.4%) patients in the second phase had neurological involvement. Altered sensorium, seizures and focal infarcts were common in the first phase, while cerebellar signs and leptomeningeal enhancement were common in the second phase. CONCLUSIONS: Neurological involvement is seen in both phases of KFD. While in the first phase it is a result of possible encephalitis/encephalopathy, the second phase involvement is possibly due to postinfectious cerebellitis or meningitis.

Difference in clinical presentation between the first and second phases of Kyasanur Forest disease: an experience from a teaching hospital in South India.

Kyasanur forest disease (KFD) is a biphasic tick-borne disease which occurs during the post-monsoon season. The patient may visit the hospital in either of the phases, and it is essential to differentiate between the two phases as the management considerations in both phases are different. This is a retrospective review of patients diagnosed with KFD who were treated by the Infectious Disease Department between September 2019 and May 2020. A total of 14 cases (16 admissions) were diagnosed during the study period by reverse-transcriptase polymerase chain reaction assay. Of these, nine cases came to our hospital during the first phase and seven (including two-readmissions) came to our hospital during the second phase. The manifestations in the first phase included high-grade fever (100%), myalgia (67%), conjunctival suffusion (33%), palatal eruptions (78%), gastrointestinal manifestations (67%), leucopenia (100%), thrombocytopenia (89%), elevated transaminases (89%), elevated creatine phosphokinase (100%) and activated partial thromboplastin time (APTT) (100%). Manifestations in the second phase were fever (57%), headache (100%), blurring of vision (29%), neck signs (71%), leukocytosis (71%), thrombocytopenia (14%), elevated transaminases (40%) and APTT (20%). The clinical symptomatology and laboratory manifestations are different in each of the two phases and can be easily identified by primary care physicians.