General Pathology Practice Flashcards

Comprehensive vocabulary flashcards covering Hematology, General Pathology, Clinical Chemistry, and Immunology for Nairobi Med School Year 2.

Microcytic hypochromic anemia

Anemia characterized by $\downarrow MCV$ and $\downarrow MCHC$, commonly caused by iron deficiency, thalassemia, anemia of chronic disease, or sideroblastic anemia.

Normocytic normochromic anemia

Anemia with normal cell size and hemoglobin concentration, typically seen in acute blood loss, hemolysis, aplastic anemia, or early stages of chronic disease.

Macrocytic anemia

Anemia characterized by $\uparrow MCV$, divided into megaloblastic (B12/folate deficiency) and non-megaloblastic (liver disease, hypothyroidism, alcohol) types.

Iron deficiency anemia laboratory findings

$\downarrow$ serum ferritin, $\downarrow$ serum iron, $\uparrow TIBC$, $\downarrow$ transferrin saturation, and $\uparrow RDW$.

Megaloblastic anemia morphology

Features macro-ovalocytes, hypersegmented neutrophils, and megaloblasts in the bone marrow.

Intravascular hemolysis clinical markers

Destruction within vessels leading to $\downarrow$ haptoglobin, hemoglobinemia, hemoglobinuria, and hemosiderinuria.

Extravascular hemolysis clinical markers

Destruction by splenic/hepatic macrophages leading to splenomegaly, unconjugated hyperbilirubinemia, and normal or mildly $\downarrow$ haptoglobin.

Sickle cell anemia mutation

A point mutation resulting in the substitution of Glutamic acid by Valine (Glu$\rightarrow$Val) at position 6 of the $\beta$-globin chain.

Howell-Jolly bodies

Nuclear remnants in RBCs seen on a peripheral smear, typically following splenic autoinfarction in sickle cell patients.

Primary hemostatic plug formation

Occurs during the platelet phase via adhesion (vWF-GPIb), activation, and aggregation.

Intrinsic coagulation pathway monitor

Activated partial thromboplastin time (aPTT), covering factors XII, XI, IX, and VIII.

Extrinsic coagulation pathway monitor

Prothrombin time (PT), involving Tissue Factor and factor VII.

Common coagulation pathway

Convergence of pathways at factor X, leading to the sequence: X$\rightarrow$V$\rightarrow$prothrombin(II)$\rightarrow$thrombin$\rightarrow$fibrinogen(I)$\rightarrow$fibrin.

DIC (Disseminated Intravascular Coagulation)

Widespread coagulation activation leading to consumption of factors/platelets, causing simultaneous thrombosis and hemorrhage; labs show $\downarrow$ platelets/fibrinogen and $\uparrow D-dimer$.

Acute leukemia diagnostic threshold

A condition defined by the presence of $\ge 20\%$ blasts in the bone marrow or blood.

Vitamin K dependent factors

Factors II, VII, IX, X, and proteins C and S, which require $\gamma$-carboxylation for activation.

Polycythemia vera

Absolute primary polycythemia caused by a $JAK2$ mutation, resulting in $EPO$-independent erythropoiesis.

Coagulative necrosis

Necrosis characterized by protein denaturation; typical of ischemic infarcts in solid organs except the brain.

Liquefactive necrosis

Necrosis characterized by enzymatic digestion; typically seen in brain infarcts and abscesses.

Apoptosis intrinsic pathway

Mitochondrial-mediated pathway triggered by DNA damage/stress, involving $Bax/Bak$, cytochrome c release, and caspase-9 activation.

Metaplasia

A reversible cellular adaptation where one differentiated cell type is replaced by another, such as columnar to squamous in smokers' lungs.

Acute inflammation cellular sequence

Margination, rolling (selectins), adhesion (integrins), transmigration (diapedesis), and chemotaxis.

Granulomatous inflammation

A specific form of chronic inflammation characterized by epithelioid macrophages, giant cells, and a lymphocyte cuff.

Virchow's Triad

The three factors contributing to thrombosis: endothelial injury, abnormal blood flow (stasis/turbulence), and hypercoagulability.

Anion gap calculation

Used to evaluate metabolic acidosis: $Na - [Cl + HCO_3]$; normal range is approximately $8-12$.

Hyperkalemia ECG findings

Peaked T waves and a widened QRS complex; carries a high risk of arrhythmia.

Diabetes mellitus diagnostic criteria

Fasting glucose $\ge 7.0\,mmol/dm^3$, random/OGTT 2hr $\ge 11.1\,mmol/dm^3$, or $HbA1c \ge 6.5\%$.PH

Troponin (I/T)

The most sensitive and specific biomarkers for myocardial injury, rising within $3-6$ hours and peaking at $24$ hours.

Type I Hypersensitivity

IgE-mediated immediate reaction involving mast cell degranulation and release of histamine and leukotrienes.

Type IV Hypersensitivity

T-cell mediated delayed reaction (24-72h) involving no antibodies; examples include the Mantoux test and contact dermatitis.

MHC/HLA Class I

Molecules found on all nucleated cells that present antigens to CD8 T cells.

Amyloidosis diagnosis

Identified via Congo red stain, which demonstrates apple-green birefringence under polarized light.

Dystrophic calcification

Calcification occurring in damaged or necrotic tissue despite normal serum calcium levels.

Metastatic calcification

Calcification in normal tissues resulting from hypercalcemia (e.g., hyperparathyroidism or renal failure).