Convert to ICD-10-CM: 
083.9 converts approximately to:
- 2015/16 ICD-10-CM A79.9 Rickettsiosis, unspecified
 
 ICD-9-CM Volume 2 Index entries containing back-references to 
083.9:
- Disease, diseased - see also Syndrome
rickettsial NEC 083.9
 - Infection, infected, infective (opportunistic) 136.9

rickettsial 083.9
 - Rickettsial disease 083.9
 - Rickettsiosis NEC 083.9