This is a 67-year-old male who presented with complaints of general weakness and easy fatiguablity for 45 days. He underwent a renal transplant 30 years prior to this presentation. He was initially on prednisolone and cyclosporine for 3 months and later changed to prednisolone and azathioprine. Following the transplant, he was asymptomatic until seven months prior to this presentation.

A CBC was performed and showed absolute lymphocyte count >5000/mm3.

Peripheral smears showed atypical lymphoid cells with intracytoplasmic large azurophilic granules (as depicted in Fig 1 and 2).

Bone marrow biopsy showed hypocellular marrow with atypical lymphoid infiltrate. Immunophenotyping by flow cytometry showed and expanded lymphoid population comprising 93%  of all cells with bright expression of CD3, CD43, CD38, TCR gamma and delta with heterogenous expression of CD16,  weak CD7 and loss of CD5, CD4, CD8.

Immunohistochemistry: The lymphoid cells were positive for CD3, TIA1 and Granzyme B and negative for CD4, CD20, CD7, CD8, CD56 and CD57 suggestive of T-cell large granular lymphocytic leukemia.

T-LGL leukemia is a rare disorder with a variable clinical course in solid organ transplant patients. Symptoms developed in more than half of patients and the most common presentation was anemia. Some T-LGL clones, especially those expressing γδTCR, were associated with severe clinical manifestations requiring the use of additional immunosuppressive agents. Nevertheless, T-LGL leukemia does not seem to impact graft and overall survival, although the development of disease-related complications and adverse effects of cytotoxic chemotherapy may pose threats to outcome of the affected patients [1].

Reference:

1. Alfano G, Fontana F, Colaci E, Mori G, Cerami C, Messerotti A, Potenza L, Luppi M, Cappelli G. T-cell large granular lymphocyte leukemia in solid organ transplant recipients: case series and review of the literature. Int J Hematol. 2019 Sep;110(3):313-321. doi: 10.1007/s12185-019-02682-2. Epub 2019 Jun 27. PMID: 31250283.