Path quick facts Flashcards
Wire looping appearance on light microscopy of renal bx
Lupus nephritis
Crescent formation in the glomeruli
Rapid progressive glomerulonephritis
Anti-GBM abs, hematuria, hemoptysis
Goodpasture syndrome (rapid crescentic GN)
Deposits of IgA in the mesangium
Post-streptococcal glomerulonephritis (remember subepithelial humps)
Lumpy-bumpy deposits of IgG, IgM, and C3 in the mesangium
Acute post-streptococcal GN
Linear pattern of IgG deposition on immunofluorescence of kidney bx
Goodpasture syndrome (hemoptysis + hematuria)
Cola-colored urine + periorbital edema
Acute Post-strep GN
Crescents of fibrin and plasma proteins on bx + c-ANCA
Granulomatosis with polyangitis
Crescents of fibrin and plasma proteins on bx + p-ANCA
microscopic polyangitis
Renal pathology associated with Henoch-Schonlein purpura
IgA nephropathy (berger dz)
Eye problems (retinopathy, lens dislocation) + glomerulonephritis + sensorineural deafness
Alport syndrome (defect in Type IV collagen)
Nephritic syndrome and nephrotic syndrome, Tram-track appearance of GBM, subendothelial IC deposits, associated with hep B, hep C, lupus, subacute endocarditis
Membranoproliferative glomerulonephritis
Most common cause of nephrotic syndrome in kids, associated with recent infection, immunization or immune stimulus, tx with corticosteriods
minimal change disease
Associated with HIV, massive obesity, higher incidence in AA and Hispanics, effacement of foot processes
Focal segmental glomerulosclerosis
GBM thickening, “spike and dome” + subepithelial deposits, can be seen with SLE
Membranous nephropathy
deposits in mesangium, show apple-green birefringence with Congo red stain
Amyloidosis (seen in MM)
Eosinophilic nodular deposits = Kimmelstiel-Wilson lesions, mesangial expansion
Diabetic glomerulonephropathy (most common cause of end stage renal dz in US)
RBC casts
glomerulonephritis
WBC casts
acute pyelonephritis
Granular “muddy brown” casts
acute tubular necrosis
Waxy casts
end-stage renal disease
Radiopaque, envelope shaped kidney stone
Calcium oxalate
What are calcium oxalate stones associated with?
Chron’s dz (malabsorption), vitamin C abuse, ethylene glycol ingestion, vit C abuse, low citrate with low urine pH
-most common stone
Tx for calcium kidney stones
thiazides –> cause Ca2+ to be retained in serum
What infections are ammonium magnesium stones associated with?
Proteus mirabilis, Staph saprophyticus, Klebsiella
Radiopaque coffin lid shaped kidney stone
AMP (struvite)
Radioluscent rhomboid or rossette shaped kidney stone
uric acid stone
What are uric acid stones associated with?
hyperuricemia –> gout, Lesch-Nyhan
Radioluscent hexagonal kidney stone
cysteine stones
What are cysteine stones associated with?
Hereditary condition that prevents reabsorption of cysteine in the proximal tubule, begins in childhood
Most common childhood kidney tumor
Wilms tumor
What is the WAGR complex?
Wilms tumor, Aniridia (absent iris), Genitourinary malformations, Mental Retardation (deletion in WT1 gene)
Risk factors associated with transitional cell carcinoma
smoking, napthylamine dyes, aniline dyes, cyclophosphamide
most common tumor of urinary tract system
Risk factors for squamous cell carcinoma of the bladder
chronic cystitis, smoking, chronic nephrolithiasis, Schistosoma haematobium
Most common renal malignancy
Renal cell carcinoma - originates from PCT cells
Risk factors for renal cell carcinoma
smoking, men 50-70
What are the paraneoplastic syndromes associated with RCC?
2’ Polycythemia - excess EPO
secrete excess PTHrP –> bone resorption
Sources of ectopic EPO production and 2’ polycythemia
“Potentially Really High Hematocrit” - Pheocromocytoma, Renal cell carcinoma, Hepatocellular carcinoma, Hemangioblastoma
Causes of polycythemia
Hypoxia - lung dz, high altitude
Ectopic EPO
Primary Polycythemia
Down syndrome
Blistering cutaneous photosensitivity, tea colored urine, hypertrichosis, facial hyperpigmentation, can be associated with alcohol or Hep C (increased LFTs)
Porphyria cutanea tarda
Defective enzyme in porphyria cutanea tarda
Uroporphyrinogen decarboxylase - converts uroporphyrinogen III to coprophyrinogen
Painful abdomen, port-wine colored urine, polyneuropathy, psychological disturbances, precipitated by drugs
Acute intermittent porphyria
Tx = heme and glucose to inhibit ALA synthase
Defective enzyme in Acute intermittent porphyria
Porphobilinogen deaminase - converts porphobilinigen to hydroxymethylbilane
Rate limiting step in heme synthesis
Delta-aminolevulinic acid synthase (ALA synthase) - requires B6 cofactor
Enzymes inhibited by lead in the heme synthesis pathway
Ferrochelatase, Delta-aminolevulinic acid dehydratase
Blue lines on gum, hyperluscent lines on long bones in X-ray, abdominal pain, growth impairment, HA, hearing problems, wrist/foot drop, encephalopathy, basophilic stippling
Lead poisoning
Tx - succimer + dimercaprol in kids, EDTA in adults
Acanthocyte (spur cell)
Abetalipoproteinemia, liver dz
Basophilic stippling
lead poisoning
Teardrop cell (dacrocyte)
Bone marrow infiltration
Bite cell (degmacyte)
G6PD def.
Echinocyte (burr cell)
Liver dz, renal dz, pyruvate kinase def
Elliptocyte
hereditary elliptocytosis
Ringed sideroblast
disorders of heme synthesis - found on BM bx
Schistocytes
DIC, TPP/HUS, HELLP syndrome - fragments of RBCs
Spherocyte
Hereditary spherocytosis
Target cells
“HALT at target” - HbC dz, Asplenia, Liver dz, Thalassemia
Heinz bodies
G6PD
caused by oxidized Hb molecules that precipitate, can become bite cells
Howell-Jolly bodies
Asplenia
-nuclear remnants found in RBCs, only 1/cell
Causes of hypochromic, microcytic anemia
iron deficiency, lead poisoning, thalassemia
Skull x-ray shows hair-on-end appearance
Beta thalassemia, sickle cell disease
decreased serum iron, increased TIBC/transferrin, decreased ferritin, decreased transferrin saturation
IDA
decreased serum iron, decreased TIBC/transferrin, increased ferritin (high stores)
AOCD
increased serum iron, increased ferritin, increased transferrin saturation
Hemochromatosis
Causes of microcytic anemia
Iron deficiency, late anemia of chronic dz, thalassemias, lead poisoning, sideroblastic anemia
Alpha-globin gene deletions, Asian and African populations, form excess beta globin chains and form HbH (four beta globin chains pair)
Alpha thalassemia
Beta-globin absent or underproduced, increase in HbF, crew cut look on x-ray due to marrow expansion, target cells, Mediterranean populations, chipmunk face
Beta thalassemia - tx with blood transfusions
minor = increased HbA2
What is the genetic cause of sideroblastic anemia?
defect in delta-ALA synthase gene (also caused by drugs, alcohol, B6 def., isoniazid)
tx - B6 supplement (cofactor for ALA synthase)
Microcytic anemia + swallowing difficulty + glossitis
Plummer-Vinson syndrome (iron deficiency with esophageal webs)
Causes of megaloblastic anemia (hypersegmented neutrophils)
Folate deficiency, B12 deficiency, orotic aciduria
-can be decreased intake, increased requirement (preggers), mtx or TMP-SMX
Neuro sx, increased homocysteine, neuro sx, megaloblastic anemia, increased methylmalonic acid, hypersegmented neutrophils
B12 deficiency
-can be seen in strick vegans, malabsorption, Diphyllobothrium latum
Increased homocysteine, megaloblastic anemia, normal methylmalonic acid, hypersegmented neutrophils
Folate deficiency
Causes of non-megaloblastic macrocystic anemia
Liver disease, alcoholism
Mechanism of AOCD
inflammation –> increases hepcidin which binds all ferroportin in macs and intestinal cells –> can’t transport iron to bone marrow for RBC synthesis
Drugs that cause aplastic anemia
Chloramphenicol, Cancer drugs, Benzene, Zidovudine (HIV tx)
Causes of aplastic anemia
Radiation Fanconi anemia Drugs Infections - EBV, Parvo B19, HIV, hepatitis Idiopathic
Pancytopenia + hypocellular bone marrow with fatty infiltrate
Aplastic anemia
-can tx with GM-CSF
Elevated creatine + normocytic anemia
renal failure (can’t make EPO)
Spherocytes on smear, splenomegaly, increased MCHC, increased RDW, + osmotic fragility test
Hereditary spherocytosis
-tx = splenomegaly
Hemolytic anemia in a newborn
think about pyruvate dehydrogenase def.
Glutamic acid –> lysine mutation in Beta-globin gene
HbC disease - milder than sickle cell dz
point mutation in beta-globin gene glutamic acid –> valine
Sickle cell anemia
Precipitating factors for HbS to polymerize in sickle cell anemia
low O2, high altitude, dehydration, acidosis
Treatment for sickle cell anemia
Hydroxyurea - increases concentration of HbF
Complications of sickle cell anemia
aplastic crisis with ParvoB19, autosplenectomy (vax for S. pneumo and Hib), splenic infarcts, Salmonella osteomyelitis, painful crisis in hands and feet or acute chest syndrome (vaso-occlusion), Renal papillary necrosis
Causes of Warm AI hemolytic anemia
congenital immune issues, CLL, EBV, HIV, SLE
-IgG ab
Causes of Cold AI hemolytic anemia
EBV mononucleosis, Mycoplasma pneumonia, EBV, CLL
-IgM ab + complement destruction
Test for AI hemolytic anemia
Coombs
- direct = testing if RBCs are coated with Ig
- indirect = testing for presence of anti-RBC Ig in serum
Painful cyanosis in fingers and toes with hemolytic anemia
Cold AI hemolytic anemia
Red urine in the morning and fragile RBCs, hemosiderinuria thrombosis
Paroxysmal nocturnal hemoglobinuria
Labs seen with von Willebrand disease
increased bleeding time and PTT
What is the defect in von Willebrand disease?
defect in vWF which normally protects Factor VIII (intrinsic pathway) –> increase PTT
defect in vWF which helps platelets form plug –> increase bleeding time
most common inherited bleeding disorder
von Willebrand disease
Lab used to diagnose von Willebrand disease
ristocetin cofactor assay - won’t see platelet aggregation
Treatment for von Willebrand disease
desmopressin - causes vWF to be released
Labs seen with DIC
schistocytes, increase in D-dimer, decrease in fibrinogen,
increase in BT, PT, PTT, decreased platelets
Causes of DIC
“STOP Making Thrombin” - Sepsis (gram -), Trauma, Obstetric complications (placental abruption, amniotic fluid embolism), Pancreatitis (acute), Malignancy, Transfusions
Clinical signs of a platelet disorder
microhemorrhages - petechiae, purpura, epistaxis, mucous membrane bleeding
increased bleeding time
Symptoms of TTP
“FAT RN” - Fever, Anemia (microangiopathic hemolytic), Thrombocytopenia, Renal Failure, Neuro symptoms
Defect in Thrombotic thrombocytopenic purpura
inhibition of deficiency in ADAMTS 13 - can’t break down large vWF multimers –> they bind platelets –> platelets aggregate and thrombosis
-generally an acute disease
Defect in Immune Thrombocytopenia
anti-GpIIb/IIIa antibodies –> splenic macs consume platelet/ab complexes –> decreased platelets
- often follows viral illness
- see megakaryocytes on BM bx
- tx with steroids or IVIG
Defect in Glanzman thrombocytopenia
defect in GpIIb/IIIa –> can’t form platelet-platelet aggregation
-normal platelet count, just increased BT
Defect in Bernard-Soulier syndrome
defective GpIb –> platelets can’t bind vWF
-normal platelet count, increased BT
Triad of HUS
thrombocytopenia, renal failure, microangiopathic hemolytic anemia
-milder form of TTP
What is a common illness that affects children before they have HUS?
E. coli O157:H7 infection causes diarrhea - produces shiga toxin
