Langerhans cell histiocytosis and multiple reticulohistiocytomas in a patient with TAR syndrome: An association not previously described

Abstract

We describe a patient with thrombocytopenia-absent radius (TAR) syndrome, multisystemic Langerhans cell histiocytosis and multiple reticulohistiocytomas. A mutational study by massive sequencing identified the Val600Glu (V600E) BRAF mutation in the Langerhans cell histiocytosis lesions, but no molecular alterations were found in the reticulohistiocytoma lesions. The concomitant presence in the same patient of more than one type of histiocytosis from two different groups recognized in the most recent Histiocyte Society classification is an extremely rare event. Our case is the first reported case of multisystemic Langerhans cell histiocytosis and multiple reticulohistiocytomas in a patient with TAR syndrome.

TAR syndrome: Clinical and molecular characterization of a cohort of 26 patients and description of novel noncoding variants of RBM8A

“…We found only 1 case of cow's milk intolerance among 15 living patients (7%), although it is reported to affect 27%–47% of TAR patients (Greenhalgh et al, 2002; Klopocki et al, 2007). Other anomalies which have been reported previously were observed in our series, including retrognathism (Houeijeh et al, 2011), scoliosis (Greenhalgh et al, 2002), facial angioma (Greenhalgh et al, 2002), hands and feet edema (Hall, 1987), and Langherans cell histiocytosis (Giordano et al, 2011; Hipólito et al, 2019). We observed clinical features which have not been associated with TAR syndrome, including syringomyelia, segmentation abnormalities of thoracic vertebrae and eye coloboma (Table S1).…”

Pediatric Acute Liver Failure Secondary to Autoimmune Hepatitis in an Infant With Thrombocytopenia-Absent Radius (TAR) Syndrome: A Case Report

“…There are many documented hematologic manifestations associated with TAR syndrome; most commonly transient leukemoid reaction with white blood cell count >35 000/µL and often associated with hepatosplenomegaly ( 1 ). Other rare reports include T-cell acute lymphoblastic leukemia (ALL), B-cell ALL, acute myeloid leukemia, and Langerhans cell histiosyctosis ( 5 , 6 ). While there are no reports of autoimmune disease or AIH in patients with TAR syndrome, TAR is very rare and it is possible that cases exist that have not been reported or that this is rather just a casual association rather than TAR leading to increased susceptibility to AIH.…”