Approximately 30% of patients with chronic hepatitis C have persistently normal serum alanine aminotransferase (ALT) levels. In most of the previous studies, the follow-up period of ALT levels did not exceed 12 months. Our objective was to redefine the terms persistently normal alanine aminotransferase (PNALT), persistently elevated ALT (PEALT), and fluctuating ALT (FLUXALT) and to determine the proportion of each group among Nile Delta patients. 348 patients infected with chronic hepatitis C were included, HCV infection was proved by a polymerase chain reaction. We studied an average of 19 ALT measurements for each participant between 2004 and 2007 with 2-month interval between successive measurements. We defined a patient as having PNALT, PEALT, or FLUXALT when all the 19 ALT levels were normal (<40 IU/L), elevated (>40 IU/L), or did not fit either of the above two categories, respectively, during the 36-month follow-up period. 73 patients had PNALT, 157 had PEALT, and 118 had FLUXALT (P<0.001). There were no significant differences regarding age, sex and body mass index. Patients with PNALT were more likely to have an Ishak fibrosis scores of < 2 while those with PEALT of 2 to 6, the third group with FLUXALT of 1 to 5 (P<0.001). 21% of patients infected with chronic hepatitis C had PNALT, and 45% had PEALT, while 34% had FLUXALT. PEALT were significantly more likely to have higher degrees of fibrosis than FLUXALT patients and consequently both groups had higher fibrosis scores than PNALT patients.