Table 4. Most frequent procedures listed on leptospirosis-associated hospitalization discharge records, United States, 1998–2009*.

Procedure†	ICD-9-CM code	No. (SE) discharge records	% (SE) discharge records
Spinal tap	03.31	408 (46)	20.5 (2.1)
Venous catheterization, not elsewhere classified	38.93	203 (32)	10.2 (1.4)
Hemodialysis	39.95	147 (27)	7.4 (1.3)
Transfusion of packed cells	99.04	124 (26)	6.2 (1.3)
Venous catheterization for renal dialysis	38.95	107 (23)	5.4 (1.2)

*ICD-9-CM, International Classification of Diseases, 9th revision, Clinical Modification (17).
†Discharge records may contain >1 listed procedure.