Karyorrhexis

Karyorrhexis After 48 h, karyorrhexis of the photoreceptor cells progressed, and widespread destruction of the photoreceptor layer occurred. From: Animal Models for the Study of Human Disease (Second Edition), 2017 Related terms: • Macrophage • Autophagy • Pyknosis • Karyolysis • Neutrophil • Tissues • Cell Death • Necrosis • Plasma Membrane John W. Harvey DVM, PhD, DACVP, in Veterinary Hematology, 2012 Pyknosis and Karyorrhexis Neutrophils that undergo programmed cell death (apoptosis) exhibit pyknosis and karyorrhexis. 359 Pyknosis involves the shrinkage or condensation of a cell with increased nuclear compactness or density; karyorrhexis refers to subsequent nuclear fragmentation ( Fig. 5-29, F). Pyknosis and karyorrhexis are degenerative changes that are often observed in nonseptic exudates. They may be seen in blood neutrophils that have had prolonged time in the circulation. Pyknotic neutrophils are reported in increased numbers in inflammatory and neoplastic disorders in humans. 423 Neutrophil hypersegmentation and pyknosis were reported in a dog with amphetamine toxicity attributed to high body temperature and accelerated apoptosis. 496 G. Peter Vooijs, ... Johan Bulten, in Comprehensive Cytopathology (Third Edition), 2008 Degenerative Changes Degenerative changes of nuclei such as folding of the nuclear membrane, karyorrhexis, karyolysis, and pyknosis in cases of inflammation must be differentiated from abnormal nuclear changes in premalignant or malignant epithel...

• Acantholysis: • Separation of cell - cell connections (desmosomes) between keratinocytes leading to single, rounded keratinocytes • Seen in pemphigus variants and related disorders • Acanthosis: • Thickening of epidermis • Elongated rete ridges usually extend into dermis • Can be regular (all rete pegs at roughly the same level) or irregular (rete pegs at different levels of the papillary dermis) • Anagen: • Hair during growth phase • Anaplasia: • Atypical nuclei (abnormal in size and shape) and pleomorphism (variation in nuclear characteristics) • Asteroid body: • Collections of eosinophilic material in sporotrichosis or star shaped inclusion in sarcoidal giant cells / other granulomatous processes • Atrophy: • Epidermal: • Decreased thickness due to reduced numbers of keratinocytes • Epidermis may appear flat at its base with loss of rete ridge pattern • May occur after inflammation / certain topical treatments • Dermal: • Thinning of dermal layer due to loss of collagen / elastin • May occur after steroids and atrophodermas • Banana bodies: • Yellow-green, banana shaped fibers in the dermis; can be due to exogenous or endogenous causes • Basal vacuolar degeneration: • Also known as liquefactive / hydropic degeneration • Small vacuoles resembling bubbles in the basal layer • Often associated with individually necrotic keratinocytes • May or may not have an associated band of infiltrate obscuring the dermoepidermal junction • Associated with vacuolar / lichenoid interfa...

A 47-year-old woman had easy bruising, menorrhagia and anemia with an unremarkable family history. Her physical examination showed a few petechiae on the legs. The white blood count was 1.4 × 10 9/L, hemoglobin 88 g/L, and platelets were 15 × 10 9/L. Peripheral blood smear had macrocytosis and hypersegmentation. Initial bone marrow was hypercellular, dyspoietic, with marked erythroid hyperplasia, slight immaturity of the granulocytic series, but with less than 5% blasts, decreased megakaryocytes, an absence of ringed sideroblasts and normal chromosomes. Laboratory tests showed no evidence of nutritional disorders, immune diseases or paroxysmal nocturnal hemoglobinuria. Myelodysplasia (multilineage dysplasia) was diagnosed and treatment was started with danazol and prednisone. Over the subsequent year, the pancytopenia fully resolved, but temporarily. Six months later, she relapsed with marked pancytopenia. A repeat marrow had prominent dyserythropoiesis with striking erythroid karyorrhexis and abundant nuclear budding (as shown). Blasts were still less than 5%. Six months after, she developed leukemic transformation. Erythroid karyorrhexis can be seen in several disorders, including congenital dyspoiesis, marked megaloblastic anemia of B12 or folate deficiency, chemical toxicity, severe hemolytic anemia, diGuglielmo's syndrome, and paroxysmal nocturnal hemoglobinuria. Karyorrhexis is also a frequent abnormality in myelodysplasia, but the degree of karyorrhexis that was obs...

Melanosis coli is a medical condition caused by the release of a pigment molecule — called lipofuscin — into the mucus membranes of the large intestine (colon). Melanosis coli isn’t life-threatening. Most likely, you won't even know that you have it. It’s detected through a What Are Melanosis Coli Symptoms? There are typically no symptoms associated with melanosis coli. The most common way that it’s discovered is through a colonoscopy, a test that is used to detect polyps or other irregularities in the colon. Melanosis coli causes a dark brown mucosal pigmentation in the proximal colon, which refers to the beginning portion of the large intestine that connects to the small intestine and the middle regions of the large intestine. However, there are some reported cases where the coloration was almost black in color. ‌ Most patients with melanosis coli also have increased rates of ‌ There's question as to whether increased polyps is a true symptom of melanosis coli. The increased rate of polyp detection could be due to the darker intestinal coloration that melanosis coli causes. This coloration change makes polyps easier to see in a colonoscopy. ‌ There's some evidence of increased rates of adenomas — non-cancerous tumors — in patients with melanosis coli. In general, these are not a cause for alarm. ‌More research is needed to determine if this condition is simply a change in coloration or a sign of deeper problems and chronic injury to the colon. What Are Melanosis Coli Cau...