Liver International ISSN 1478-3223
Letter to the Editor DOI:10.1111/liv.12585 Liver Int. 2014: 34: 1446
Anti-ribosomal P protein antibody: an autoreactivity devoid of prognostic value in patients with autoimmune hepatitis To the Editor: We read with great interest the paper ‘Antiribosomal P protein: a novel antibody in autoimmune hepatitis’ by et al. Calich et al. (1), which suggests a relevant prognostic value for such a reactivity in patients with autoimmune hepatitis (AIH). In particular, the Authors state that ‘this antibody appears to predict the patients with worse AIH prognoses’. Nevertheless, this assertion is not substantiated by the data presented. Of the 93 AIH patients studied, 9 (9.7%) were positive for IgG anti-C22 ribosomal P peptide; of these 9 AIH patients with anti-ribosomal P protein antibody, 4 (44.4%) were already cirrhotic at the time of AIH diagnosis, whereas among the remaining 84 AIH patients without anti-ribosomal P protein reactivity, 24 (28.5%) had cirrhosis at diagnosis, according to Table 1. The Authors state that ‘the evaluation of the outcomes revealed a significantly higher frequency of cirrhosis in the anti-rib P-positive group compared with those patients without this antibody (100 vs. 60.0%, respectively, P = 0.04)’ and conclude that ‘the observed predictive value of this antibody for AIH severity appears to be a promising tool for the management of these patients’. Unexpectedly, this claim is in contrast with the reported results, as the data provided in Table 1 and in the text do not fit with the numbers shown in Table 2. In Table 1 (and in the text), 4 of 9 anti-rib P-positive patients are reported as already having cirrhosis at diagnosis; therefore, it is logical to assume that cirrhosis could newly develop in no more than the remaining 5 anti-rib P-positive patients, whereas in Table 2, inexplicably, 7 of 7 (100%) anti-rib P-positive patients are reported to have developed cirrhosis as an
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outcome of their liver disease. No mention of patients lost during follow-up is made. As far as the anti-rib P-negative AIH patients are concerned, among the 84 patients reported in Table 1, twenty-four were cirrhotic at diagnosis; therefore, it is logical to assume that cirrhosis could be an outcome only in the remaining 60 patients. According to Table 2, cirrhosis developed in 48 of 80 patients, whereas the correct number of non-cirrhotic AIH patients without anti-rib P antibody at diagnosis should be 60. Again, no mention of patients lost during follow-up is made. Overall, cirrhosis appears to have developed in 5 of 5 (100%) anti-rib P-positive AIH patients and in 48 (80%) of 60 anti-rib P-negative AIH patients (P = 0.5746, Fisher’s exact test). If the extrapolation of these data is correct, the anti-ribosomal P protein antibody is a novel autoreactivity, which, however, fails to bear any prognostic value in patients with AIH. Acknowledgement
Conflict of interest: The authors do not have any disclosures to report.
Luigi Muratori, Chiara Masi and Paolo Muratori Department of Medical and Surgical Sciences, Alma Mater Studiorum - University of Bologna, Sant’Orsola-Malpighi Hospital, via Massarenti 9, Bologna, Italy
Reference 1. Calich AL, Viana VS, Cancado E, et al. Anti-ribosomal P protein: a novel antibody in autoimmune hepatitis. Liver Int. 2013; 33: 909–13.
Liver International (2014) © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Letter to the Editor DOI:10.1111/liv.12585 Liver Int. 2014: 34: 1446
Anti-ribosomal P protein antibody: an autoreactivity devoid of prognostic value in patients with autoimmune hepatitis To the Editor: We read with great interest the paper ‘Antiribosomal P protein: a novel antibody in autoimmune hepatitis’ by et al. Calich et al. (1), which suggests a relevant prognostic value for such a reactivity in patients with autoimmune hepatitis (AIH). In particular, the Authors state that ‘this antibody appears to predict the patients with worse AIH prognoses’. Nevertheless, this assertion is not substantiated by the data presented. Of the 93 AIH patients studied, 9 (9.7%) were positive for IgG anti-C22 ribosomal P peptide; of these 9 AIH patients with anti-ribosomal P protein antibody, 4 (44.4%) were already cirrhotic at the time of AIH diagnosis, whereas among the remaining 84 AIH patients without anti-ribosomal P protein reactivity, 24 (28.5%) had cirrhosis at diagnosis, according to Table 1. The Authors state that ‘the evaluation of the outcomes revealed a significantly higher frequency of cirrhosis in the anti-rib P-positive group compared with those patients without this antibody (100 vs. 60.0%, respectively, P = 0.04)’ and conclude that ‘the observed predictive value of this antibody for AIH severity appears to be a promising tool for the management of these patients’. Unexpectedly, this claim is in contrast with the reported results, as the data provided in Table 1 and in the text do not fit with the numbers shown in Table 2. In Table 1 (and in the text), 4 of 9 anti-rib P-positive patients are reported as already having cirrhosis at diagnosis; therefore, it is logical to assume that cirrhosis could newly develop in no more than the remaining 5 anti-rib P-positive patients, whereas in Table 2, inexplicably, 7 of 7 (100%) anti-rib P-positive patients are reported to have developed cirrhosis as an
1446
outcome of their liver disease. No mention of patients lost during follow-up is made. As far as the anti-rib P-negative AIH patients are concerned, among the 84 patients reported in Table 1, twenty-four were cirrhotic at diagnosis; therefore, it is logical to assume that cirrhosis could be an outcome only in the remaining 60 patients. According to Table 2, cirrhosis developed in 48 of 80 patients, whereas the correct number of non-cirrhotic AIH patients without anti-rib P antibody at diagnosis should be 60. Again, no mention of patients lost during follow-up is made. Overall, cirrhosis appears to have developed in 5 of 5 (100%) anti-rib P-positive AIH patients and in 48 (80%) of 60 anti-rib P-negative AIH patients (P = 0.5746, Fisher’s exact test). If the extrapolation of these data is correct, the anti-ribosomal P protein antibody is a novel autoreactivity, which, however, fails to bear any prognostic value in patients with AIH. Acknowledgement
Conflict of interest: The authors do not have any disclosures to report.
Luigi Muratori, Chiara Masi and Paolo Muratori Department of Medical and Surgical Sciences, Alma Mater Studiorum - University of Bologna, Sant’Orsola-Malpighi Hospital, via Massarenti 9, Bologna, Italy
Reference 1. Calich AL, Viana VS, Cancado E, et al. Anti-ribosomal P protein: a novel antibody in autoimmune hepatitis. Liver Int. 2013; 33: 909–13.
Liver International (2014) © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
