Epstein-Barr virus (EBV) positive classical Hodgkin lymphoma of Iraqi children: an immunophenotypic and molecular characterization of Hodgkin/Reed-Sternberg cells

BACKGROUND

Classical Hodgkin lymphoma (cHL) in children is often associated with EBV infection, more commonly in developing countries.

PROCEDURE

Here we describe the histological, immunohistochemical, and molecular features of 57 cases of HL affecting Iraqi children under 14 years of age.

RESULTS

Histologically, 51 cases were classified as cHL of Mixed Cellularity and Nodular Sclerosis subtypes (MC = 69%; NS = 31%), and 6 cases as Nodular Lymphocyte Predominant HL (NLP-HL). EBV infection of H/RS cells was demonstrated in 44 of 51 cases of cHL (86%), and was more common in MC than in NS (97% vs. 63%; P = 0.0025). The immunophenotypic profile of H/RS cells was similar in MC and NS, and was not influenced by EBV infection; H/RS cells were consistently positive for PAX-5 and to a lesser degree for other B cell markers including CD20/CD79a, OCT-2, and BOB-1. Clonal IGH rearrangements were detected in 14 of 38 cHL (37%), with no significant difference between MC and NS cases, and with no association with the EBV status. Oligoclonal/monoclonal TCRγ rearrangements were present in 28 of 38 cases (74%), suggestive of restricted T cell responses.

CONCLUSIONS

Our findings indicate that cHL occurring in Iraqi children is characterized by immunohistochemical and molecular features undistinguishable from those present in cHL occurring elsewhere in the world. Moreover, the high incidence of EBV-infected H/RS cells and frequent occurrence of restricted T cell responses might be indicative of a defective local immune response perhaps related to the very young age of the children.

The association between juvenile autoimmune hepatitis and HLA-DRB1 alleles: Iraqi tertiary center experience

Aim of the study

To highlight the impact of the human leukocyte antigen (HLA) allele on susceptibility and prevention of autoimmune hepatitis (AIH) in Iraqi children.

Material and methods

We conducted a prospective study from children attending the Gastroenterology and Hepatology Clinic of Children’s Welfare Teaching Hospital over five years from the first of September 2015 to the thirty-first of August 2020. It included 19 patients with AIH; their age (at time of diagnosis) ranged between 3 and 16 years, with a female predominance of 78.9%. The diagnosis was made by clinical, serological, and histological features. In addition, 20 age- and sex-matched unrelated subjects of the same ethnic background were selected randomly from healthy individuals undergoing checkup as controls.

Results

19 patients diagnosed with AIH were included in this study, and 20 age- and sex-matched healthy controls, with a female predominance of 78.9%. The commonest autoantibodies found were smooth muscle antibody (SMA) in 13 (68.4%), antinuclear antibody (ANA) in 11 (57.9%). In AIH type 1, PCR showed higher frequencies among patients with HLA-DRB1*03, HLA-DRB1*04, HLA-DRB1*13 alleles in patients with AIH; moreover DRB1*11 and DRB1*15 were less frequent than in the control group. Frequency of HLA-DRB1*04 was 28% and HLA-DRB1*13 was 20% in AIH type 2 patients; HLA-DRB1*13 and HLA-DRB5 showed frequency of 25% for both and HLA-DRB4 frequency was 18.7%.

Conclusions

HLA-DRB1*13, DRB1*04, and DRB1*03 are susceptibility alleles for the development of AIH type 1, while HLA-DRB1*13, HLA-DRB4 and DRB5 are susceptibility alleles for the development of AIH type 2 in Iraqi children.