Extra 2 Flashcards
Most common thyroid cancer
Papillary - can be caused by radiation
Types of non functional thyroid cancer
Papillary
Follicular - due to low iodine
Hurthe - seen in inflammation
Describe medullary thyroid cancer
Arise from parafollicular cells
Associated with MEN 2a or 2b
Spindle cells produce calcitonin + serotonin causing diarrhea
Describe anaplastic thyroid cancer
Altered cells unlike normal ells
Pleomorphic giant cells
Most aggressive
Dx of thyroid cancer
US
Increased calcitonin
Radioiodine scan
FNA
Mechanism of neuroblastoma
common in <5 y/o
Arises from neural crest cells - don’t differentiate
Arise in adrenal gland
3 types: undifferentiated (small blue cells), poorly differentiated + differentiated (Schwannian stroma)
S+S of neuroblastoma
Fever, wt loss, sweating, fatigue
Large, painful abdo mass
Mets causing basal skull fractures = racoon eyes
Dx of neuroblastoma
HMA + VMA increased
CT
Tx of neuroblastoma
Surgery + chemo
Describe PNETS
Linked to MEN 1
Non functional - cause jaundice, asymptomatic
Functional - insulinoma or gastrinoma
Describe a gastrinoma
Increased gastrin = Zollinger Ellison syndrome
Peptic ulcers + steatorrhea
Mechansim of carcinoid syndrome
Cancers arising from neuroendocrine cells - tumors in GI tract, lung + ovaries + liver mets
Produce serotonin, histamine, bradykinin + prostaglandins
S+S of carcinoid syndrome
Itching Diarrhea Flushing SOB Pulmonary stenosis Serotonin = pellagra + bronchoconstriction
WORSENED by alcohol or stress
Dx + Tx of carcinoid syndrome
CT or octreoscan
Surgery or chemo
Describe MEN 1
Parathyroid, pancreatic + pituitary tumors
Parathyroid = increased calcium
Pancreatic = increased gastrin (ulcers), insulin (hypoglycaemia) or glucagon (hyperglycaemia)
Pituitary adenomas
Describe MEN 2a
Thyroid medullary, pheochromocytoma, parathyroid adenoma
Thyroid = increased calcitonin Pheo = increased adrenaline
Describe MEN 2b
Thyroid medullary, pheochromocytoma + neuromas
Neuromas = skin, mouth, tongue, lips etc
What is Whipple’s triad?
Hypoglycaemia with fasting or exercise
Reversal of S+S with glucose
Low BM
Means there is an insulinoma
Dx of Zollinger Ellison
Increased gastrin after secretin
Describe Peutz Jeghers syndrome
Auto dominant
Polyps in GI tract can lead to colon cancer + increased risk of breast, pancreatic, lung, ovaries + testes
Also causes melanotic macules on mouth, lips + gentials
Describe juvenile polyposis syndrome
Develop hamartomas - sessile or pedunculated
Also causes hypotonia + macrocephaly
Mechanism of primary sclerosing cholangitis
Inflammation causing fibrosis + dilation of bile ducts Looks like beading Onion skin on histology Associated with IBD Increased IgM + pANCA
S+S of primary sclerosing cholangitis
Bile in blood causing pruritis, increased conjugated bilirubin + increased ALP + GGT
Dx + Tx of primary sclerosing cholangitis
ERCP + liver transplant
Mechanism of haemochromatosis
Primary = hereditary Secondary = too many transfusions
Too much iron absorbed, causing iron deposits in liver that produce free radicals
Cause fibrosis + cirrhosis, T1DM, malabsorption, cardiomyopathy, joint disease, bronzed skin + gonadal dysfunction
Lab results for haemochromotosis
High ferritin, transferrin + iron
Low TIBC
Dx of haemochromotosis
Liver biopsy
Tx of haemochromotosis
Phlebotomy + deferoxamine
Mechanism of Wilsons disease
Failure to excrete excess copper in bile or urine
Causes deposits in tissues;
Brain = basal ganglia causing movement disorder or in cerebral cortex causing dementia
Cornea = Kaiser Fleischer rings
Liver - hepatitis / cirrhosis (1st presentation in kids)
Dx + Tx of Wilsons
Dx = reduced ceruloplasmin, increased copper in urine
Tx with copper chelators (penicillamine, trientine, zinc)
Mechanism of sideroblastic anemia
Build up of iron in RBC causing increase in immature rbc
Congenital is X linked
Acquired due to excess alcohol, lead poisoning or low B6 (due to isoniazid use)
Pappenheimer bodies in mitochondria
S+S of sideroblastic anemia
Fatigue, diarrhea, ckd, cirrhosis, heart disease
Dx + tx of sideroblastic anemia
Dx = pappenheimer bodies on smear
high iron, high ferritin, low TIBC
Tx = pyridoxine, thiamine, folic acid, defuroxamine
Mechanism of aplastic anemia
Autoimmune destruction of haematopoitic stem cells causing pancytopenia due to chemo, radiation, toxins, EBV, HIV
Also due to Fanconi’s anemia
Dx + Tx of aplastic anemia
Dx = increased EPO, decreased reticulocytes, bone marrow biopsy Tx = stem cell transplant or ciclosporin
Mechanism of G6PD deficiency
Destruction of RBC due to defective G6PD enzymes
X linked recessive
Protective against malaria due to reduced half life
causes hemolytic anemia which is worsened by free radical production from infections, fava beans, soy, quinines
S+S of G6PD deficiency
Asymptomatic until times of stress
then jaundice + anemia
Dx + Tx of G6PD def
Dx = reduced RBC, increased reticulocytes, increased LDH + bilirubin, decreased haptoglobin
Coombs test negative
Enzyme assay
Tx = hydration + transfusion
Describe factor V leidin
Auto dominant, causes vte
dx = PTT shortened or protein C functional assay
Mechanism of antiphospholipid syndrome
Autoimmune, associated with SLE
Hypercoagulable state causing arterial thrombosis + Libman Sachs endocarditis
Also causes CKD, livedo reticularis, miscarriage, neuro S+S
Dx + tx of antiphospholipid syndrome
Dx = 1 clinical (hx of thrombosis or pregnancy complications) + 1 lab (presence of anticardiolipin, anti-beta 2 glycoprotein ab or lupus anticoagulant)
Tx = aspirin/ warfarin/ heparin
Mechanism of ITP
Autoimmune - spleen produces IgG Ab
Acute = affects kids after viral infection
Chronic = affects women, triggered by hep C, HIV or lupus
Tx of ITP
Steroids or IVIG
Mechanism of SLE
ANA +
Ag + Ab complex deposits
Dx of SLE
4 of 11 criteria:
1) malar rash
2) discoid rash
3) photosensitivity
4) ulcers in mouth/ nose
5) serositis (pleuritis, pericarditis)
6) arthritis
7) renal disease
8) seizures or psychosis
9) haem disease (pancytopenia)
10) ANA +
11) Anti smith, anti-dsDNA, anti-phospholipid
S+S of polymyositis
Photosensitive macular rash
Mechanics hands
Gottron’s papules (rough red papules on fingers)
Respiratory muscle weakness
Dx of polymyositis
ANA +
Jo +
Anti Mi2 +
mechanism of pagets disease of bone
Increased bone remodelling leads to deformities
Can be triggered by measles
S+S of Pagets disease of bone
Skull; hearing loss, vision loss
Lumbar spine, pelvis + femur = nerve pain, kyphosis, osteosarcoma
Describe osteochondroma
Males <25
Benign
Arises from growth plate, forms exostosis
Typically metaphysis of long bones
Describe giant cell tumor of bone
RF: trauma + radiation
Epiphyses of long bones
Benign
Describe osteoblastoma
Benign
Forms a nidus (collection of vessels, trabeculae, osteoid)
Describe osteoid osteoma
Benign
Worse at night
Produces prostaglandins and causes pain
Describe osteosarcoma
Pleomorphic osteoblasts form increased osteoid tissue in metaphyses
Common in teens
Linked to retinoblastoma + Li-Fraumeni
Malignant
Describe Ewing’s sarcoma
10-20 y/o
Malignant
Arise from small round blue cells
Commonly affects femur and sacrum
Describe chondrosarcoma
Malignant
Affects elderly
Affects pelvis + long bones
causes bone pain, swelling and fractures
X ray findings for osteochondroma, giant cell tumors, osteosarcoma, ewings sarcoma + chondrosarcoma
osteochondroma = exostosis giant cell tumors = soap bubbles osteosarcoma = sun burst + codmans triangle ewings sarcoma = onion skin chondrosarcoma = moth eaten
