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(cell and molecular biology)
Fragmentation of a nucleus with scattering of the pieces in the cytoplasm.



the breakdown of a cell nucleus into parts; one of the intermediate stages of necrobiosis (after karyopyknosis and before karyolysis) that precedes the death of a cell. The nuclear membrane is destroyed and the nucleic acids show up asseparate clumps in the cytoplasm.

References in periodicals archive ?
ONL nuclear deformations (arrows) were observed in (A) control ONL nucleus and as (B) nucleolus condensation, (C) karyolysis, (D, E pyknosis, and (F) karyorrhexis.
Extra caution should be taken to strictly apply the morphological criteria of circumferential trophoblastic proliferation, hydropic changes, scalloped villi and stromal karyorrhexis for diagnosis (15).
In SLE, the enlarged lymph nodes may also contain areas of necrosis and karyorrhexis, but they typically show follicular hyperplasia with an abundance of granulocytes and plasma cells.
Patients with a high activity index and the presence of karyorrhexis were more likely to experience recurrent disease.
Intravascular karyorrhexis When the nucleus of a blood vessel cell disintegrates, the cell's genetic material (chromatin) fragments This change usually is found in cases where death occurred more than six hours before delivery.
These inclusions were sometimes associated with nuclear pyknosis and karyorrhexis, but again no etiological agent was detected.
On higher magnification, the necrotic areas demonstrated single-cell necrosis and abundant karyorrhexis (figure 2, B).
This necrosis was characterized by lymphocytic karyorrhexis in the white pulp, and fibrinoid necrosis, congestion, and endothelial cell swelling in the red pulp, accompanied by cell debris.
38) According to the grading scheme proposed by Evans et al, (24) viable pancreatic cancer cells can show cytoplasmic or nuclear swelling, multiple nuclei, and cytoplasmic vacuolization, whereas nonviable cancer cells have bizarre, hyperchromatic, pyknotic nuclei usually with swollen, vacuolated, or deeply eosinophilic cytoplasm and exhibit karyorrhexis.
Dysplasia Findings Diagnosis 1 RBC: megaloblastoid, 65% RS; t-MDS Meg: small, hypolobated 2 RBC: nuclear irregularity and t-MDS karyorrhexis, cytoplasmic vacuolization, 8% RS; Myeloid: nuclear atypia, cytoplasmic hypogranularity and vacuolization, pseudo-Pelger-Huet nuclei; Meg: small, hypolobated, clustered 3 RBC: megaloblastoid, nuclear budding, t-AML arising cytoplasmic vacuoles, 52% from t-MDS nucleated RBC precursors Myeloid: blasts with rare granules, no Auer rods Meg: small, hypolobated, clustered Case No.
The resolution is low, and cytologic features such as chromatin texture, presence of pyknosis or karyorrhexis, nucleolar size, or disorganized cytoskeletal organization cannot be seen.
The cellular variant is defined by the presence of at least one glomerulus with segmental endocapillary proliferation occluding lumina, with or without karyorrhexis (Figures 4 and 5).