MayGrünwaldGiemsakleuring

The May-Grünwald-Giemsa stain, commonly abbreviated as MGG stain, is a Romanowsky-type differential stain used in hematology and cytology to visualize cells on blood, bone marrow smears, and various cytology preparations. It combines elements of the May-Grünwald stain with the Giemsa stain to produce distinct color differentiation of cellular components, aiding morphological assessment.

The stain works by using a sequential combination of dyes that include methylene blue, eosin Y, and azure dyes in a buffered medium. The May-Grünwald component provides initial staining, while the Giemsa component, with azure dyes, enhances nuclear detail and cytoplasmic contrast. The typical result is blue to purple nuclei and a range of cytoplasmic colors from pink to violet, depending on cell type and content. The procedure generally involves fixing slides in methanol, briefly staining with May-Grünwald solution, followed by a buffered Giemsa stain, and final rinsing and drying.

MGG staining is widely employed for differential leukocyte counts, identification of malaria and other parasites in blood smears, and evaluation of hematologic disorders in bone marrow aspirates and cytology specimens. It is valued for producing clear nuclear detail together with discernible cytoplasmic features, supporting classification of white blood cells and assessment of cellular morphology in routine diagnostics.

Variants and related methods include Wright, Giemsa, and Wright-Giemsa stains, as well as laboratory adaptations that adjust pH and staining times to optimize results. While commonly used, the technique requires careful preparation and quality control of reagents and buffers to ensure consistent staining.