Potential viral pathogenic mechanism for new variant inflammatory bowel disease

I write in relation to our paper that was published in the April 2002 issue of Molecular Pathology.¹ When generating data for this manuscript, we tested samples and controls provided by our collaborators at the Royal Free Hospital, London.

Before the paper was published (January 2002), we became concerned that four samples included in the “control category” might not have been correctly categorised. We immediately sought to clarify the situation. While our investigation was ongoing, we decided to test four additional controls, which matched the diagnostic classification of the control samples under investigation. They tested negative, so the overall data remained unchanged.

We later established that we were correct in our suspicion that the original four controls had been inaccurately grouped. For the avoidance of doubt, those four cases tested negative for measles virus. They were as follows:

• Three “normal” biopsies that should have been classified as “autistic enterocolitis”.

• One “Crohn’s” biopsy that should have been classified as “normal”.

These samples did not form part of the testing cohorts described in the paper, having been substituted by controls whose diagnosis matched that described in the text.

To avoid confusion, if these samples had been included in our paper, the results of table 2 ▶ would have read as follows.

Table 2.

Summary of TaqMan RT-PCR and RT in situ PCR results (original)

	TaqMon RT-PCR positive	In situ PCR positive
Affected patients	70 (91)	42 (57)
Controls
Normal controls	0 (19)	1 (5)
Mild non-specific change	0 (13)	NT
Lymphonodular hyperplasia	0 (3)	NT
Appendicectomies	4 (26)	NT
Ulcerative colitis	0 (1)	NT
Crohn’s disease	0 (8)	NT

Total number of patients tested in parentheses.

NT, not tested; RT-PCR, reverse transcription polymerase chain reaction.

For comparison, the original table 2 ▶ is attached below. We apologise for any confusion caused but are anxious to document precisely the data that were presented to us and the results that we obtained.

Table 1.

Summary of TaqMan RT-PCR and RT in situ PCR results (revised)

	TaqMon RT-PCR positive	In situ PCR positive
Affected patients	70 (94)	42 (57)
Controls
Normal controls	0 (20)	1 (5)
Mild non-specific change	0 (13)	NT
Lymphonodular hyperplasia	0 (3)	NT
Appendicectomies	4 (26)	NT
Ulcerative colitis	0 (1)	NT
Crohn’s disease	0 (8)	NT

Total number of patients tested in parentheses.

NT, not tested; RT-PCR, reverse transcription polymerase chain reaction.