Pseudo‐Chédiak‐Higashi inclusions together with Auer rods in acute myeloid leukemia

Abstract

An 8-year-old Iraqi male presented with fever and pallor of 2-months duration. There was no lymphadenopathy, splenomegaly or hepatomegaly. A full blood count showed: hemoglobin concentration 6.9 g/dl, white blood cell count 1.5 3 10 9 /l and platelet count 217 3 10 9 /l. Examination of a bone marrow aspirate showed acute myeloid leukemia (AML) with little maturation; blast cells were 85% of nucleated cells, and the case was classified as FAB (French-American-British) M1 AML. An unusual feature was the presence not only of Auer rods (left) but also of pseudo-Ché diak-Higashi inclusions, which on a Romanowsky stain varied from pink to deep purple (right). In addition to typical thin Auer rods there were also thick rodshaped inclusions (left and right).Pseudo-Ché diak-Higashi inclusions are observed occasionally in AML 1 (including acute promyelocytic leukemia) and also, rarely, in refractory anaemia with excess of blasts. 2 The inclusions are formed by fusion of azurophilic (primary) granules and show myeloperoxidase activity and Sudan black B staining. On ultrastructural examination they are heterogeneous and, in contrast to the inclusions seen in the inherited anomaly, contain rod-shaped structures showing periodicity. 1 The diagnostic significance of these inclusions is likely to be similar to that of Auer rods, indicating either AML or a high grade myelodysplastic syndrome.

Multiple Pseudo-Chediak-Higashi Inclusions Associated with MYC Deletion in a Patient with Acute Myeloid Leukemia

“…The pseudo-Chédiak-Higashi (PCH) anomaly is a large pink or purple cytoplasmic granule that has only been rarely described in acute myeloid leukemia (AML) [1,2,3,4,5,6,7,8,9]. These giant granules are azurophilic and myeloperoxidase positive.…”

Diagnosis of Acute Leukemia in Under-Resourced Laboratories

“…However, when using SBB stain many of the "apparently" agranular blasts turn to be granular. Pathognomonic signs of AML that can be seen with Romanowsky stain and more frequently with SBB stain include SBBpositive granules, Auer rods, atypical "thick" Auer rods, pseudo-Chediak-Higashi inclusions (Abdulsalam et al, 2011a) (Image 1) and rectangular crystalline structures (Merino & Esteve, 2005) . Image 1.…”

Acute Myeloid Leukaemia with Giant Inclusion: Pseudo-Che´Diak-Higashi Anomaly

“…In the literature, cases with pseudo-Che´diak-Higashi inclusions were reported rarely. This inclusions can be seen in AML or myelodysplastic syndrome (MDS) (refractory anaemia with excess blasts) (1)(2)(3)(4). Myeloperoxidase activity-Sudan black B staining is positive for this inclusions that is form of azurophilic (primary) granules and composed of micro-structures like Auer bodies (2)(3)(4)(5).…”