parathyroid disorder/paget dz Flashcards
paget disease
localized disorder of bone remodeling
-begins with excessive bone resorption followed by an increase in bone formation
what is a bone feature of paget disease?
woven bone- structurally disorganizzed mosaic of bone that is weaker, larger, less compact, more vascular and more likely to fracture
what are the clinical features of paget disease?
most are asx;
- bone pain (most common sx)
- secondary osteoarthritis (when it occurs around a joint)
- excessive warmth (due to hypervascularity)
- neurologic complications (compression of neural tz)
what bones are most likely to have paget disease?
single bone but is more frequently multifocal. It has a predilection for the axial skeleton (ie, spine, pelvis, femur, sacrum, and skull, in descending order of frequency), but any bone may be affected.
-After onset, Paget disease does not spread from bone to bone, but it may become progressively worse at preexisting sites.
etiology of paget
widely unknown, maybe genetic/enviormental
- white ppl
- measles, RSV
what are the three phases of Paget dz?
lytic
mixed lytic and blastic
sclerotic
what is the lytic phase of PD?
normal bone is resorbed by abnormal osteoclasts (larger more nuclei)
what is the mixed phase?
rapid increases in bone formation from numerous osteoblasts, but normal looking
BUT new bone is abnormal w/ collagen fibers depositid in a bad fashion, rather than linerally
high degree of bone turnover
what is the sclerotic phase?
woven bone patter- allows bone to be infiltrated by excessive fibrous connective tissue and BV- eventually this burns out (sclerotic) and the condition becomes quiescent
what are some complications if the skull is involved in PD?
Deafness Vertigo Tinnitus Dental malocclusion Basilar invagination Cranial nerve disorders
verterbral involvment of PD?
nerve root compressions or cauda equina syndrome
lab findings in Paget dz?
serum Ca, Phosphorous, and PTH are all normal
*might see hypercalcemia
what are some markers of bone turnover that are usefule to monitor in pt w/ aget dz?
- Bone-specific alkaline phosphatase (marker of bone formation)
- Deoxypyridinoline (marker of bone resorption)
- N -Telopeptide of type I collagen (marker of bone resorption)
- Alpha-alpha type I C-telopeptide fragments
tx of paget dz
tx isn’t curative but control progression
bisphosphonate tx
Ca, vit D , NSAIDs
drug tx of PD
Etidronate
Pamidronate
Alendronate
Tiludronate
Risedronate
Zoledronic acid
Salmon calcitonin
Pamidronate and salmon calcitonin are administered parenterally. (Human calcitonin is no longer available.
what does PTH do?
causes serum Ca to increase by mobilizing osteoclasts, stimulates the kidneys to resorb Ca and increases GI absorption of Ca
what is the main cause of primary hyperparthyroidism?
benign parathyroid gland adenomas
what are other causes of primary HyperPT?
hyperplasia, carcinomas
what is the etiology of hyperPT?
W>M, incidence increases after 50 yo
what is the most common cause of hypercalcemia in hospitalized pts?
malignancy
what other disorders might cause hypercalcemia?
renal failure milk-alkali syndrome multiple myeloma head-neck-lung Ca sarcoidosis TB medications(thiazides, Ca, Vit D, lithium) Hodgkin lymphoma adrenal insufficiency prolonged bed rest hyperthyroidism (secondary hyperPT)
hyperPT and CKD?
secondary hyperPT is caused by hyperphosphatemia that increases ionized Ca levels and decreased renal production of active vit D
sx of hyperPT/
mild-asx
thrist, anorexia, N, V, abdominal pain, constipation, fatigue, anemia, weight loss, PUD, pancreatitis, HTN, depressed tendon reflexes
polydypsia and polyuria caused by hypercalcemia induced nephrogenic DI
“stones bones groans and psychiatric moans”
stones: renal loss of Ca and Phosphate
bones: bone loss from PTH (cortical bone or diffuse bone demineralization=traecular bone increase)
pathologic fractures=cystic bone lesion (jaw)
groans: increased GI absorption and abdominal cramps
moans: irritability, psychosis, depression
dx of Hyper PT?
primary: Ca > 10.5 and phosphate <2.5 with PTH > 55
(adjusted for albumin)
secondary: elevated Ca w/ low pH (malignancy)
what does extreme elevations of Ca and PTH indicate?
parathyroid CA!!!!
imaging studies in hyperPT?
US, CT, MRI, sestamibi scan (not really for dx, but for surgery if thinking PT adenoma)
what do pts need to be screened for before beginning tx of hyperPT?
familial benign hypocalciuric hypercalcemia- 24 hours urine Ca and creatinine
what if the t has low bone mineral density, a normal serum Ca, and elevated PTH levels be assessed for?
secondary hyperP from vit D or ca deficiency, hyperphosphatemia, renal failure
what may an EKG find in a pt with hyperPT?
prolonged PR interval, shortened QT interval, bradyarrhythmias, heart block, asystole
tx of hyper PT?
asx: keep active, avoid immobilzation, fluids
avoid thiazide diuretics, large doses of Vit A and d, Ca containing antacids and supplements
what should you monitor in a pt with hyper PT?
serum Ca and albumin levles, kidney fxn, urinary Ca excretion, bone density
+/- bisphosphonates, vit D
tx of acute hypercalcemic crisis?
IV hydration and vsiphosphonates, furosemide (may help excrete Ca )
tx of sx primary disorder?
parathyroidectomy (hypocalcemia and transint hyperthyroidism may occur later on
when is surgery indicated?
- sx hypercalcemia (proximal muscle wkns, gaint distrubance, atrophy, hyperreflexiz)
- hx of life threatening hyperca
- adjusted ca > 1 mg/dL above upper limit
- urianry ca excretion > 400 mg in 24 hours
- creatinine clearance less than 60 ml
- bone density consistent w/ osteoporosis or previous fragility bone frx
- age younger than 60
- osteitis fibrosa cystica
- nephrolithiasis
- preg
- parathyroid carcinoma
hypoparathyrodims (acquired)
most common after parathyroidectomy or thyroidectomy
other causes of hypoparathyroidism
autoimmune dz, heavy metal toxicity (wilson, hemochromatosis)
thyroiditis
hypoMg (chronic alcoholism)
DiGeorge syndrome
congenital cause of hypocalcemia arising from PT hypoplasia, thymic hypoplasia, and outflow tract defects of the heart
what is congenital pseudohypoparathyroidism
group of disorders charachterized by alteration in serum calcium related to resistance to PTH
CF of hypoPT
- tetany
- carpopedal spasma
- muscle or abdominal cramps
- paresthesias
- teeth, nail, hair defects
- hyperreflexia
Chovstek sign?
contraction of eye, mouth, or nose mucles elicited by tapping along the course of the facial nerve anterior to the ear
Trousseau sign?
spasm n the hand and wrist w/ compression to the forearm
chronic hypoPT sx
lethargy anxiety parkinsonism mental retartdation personality changes blurred vision caused by cataracts
dx studies of hypoPT
decreased PTH, ajusted serum Ca and increased phosphate levels
Mg may also be low (worsen sx)
alkaline phosphate normal
EKG changes of hypoPT
prolonged QT and T-wave abnormalities
radiography of hypo PT
chronic increased bone mineral density, especially in the lumbar spine and skull
tx of hypoPT
PTH -tx of osteoporosis
-correct hypocalcemia w/ Ca and vit D
**IV Ca Gluconate
oral Ca (1-2 g/day) and vit D=serum Ca at 8-8.6
thiazide diuretics
what should be avoided in hypoPT
phenothiazines and furosemide
how do you tx tetany caused by hypoPT?
airway maintenance and slow administraion of IV calcium gluconate
tx of sever cases that don’t respond to anything else
PTH-teriparatide, Natpara
ADR: paresthesia, hypocalcemia, HA, NVD, arthralgia, pain in extremity
warnings: OSTEOCARCOMA
what is calcium gluconate also used for?
black widow bits to tx muscle cramping
what is calcium gluconate contraindicated for?
v fib or hypercalcemia
calcium gluconate ADR
tinglilng, heat sensation, chalky taste
calcium glconate DR?
arrhythmia w/ digoxin
binds tetracycines
ceftriaxone precipitates if mexed together
calcitriol ADR
Hypercalcemia, hypercalciuria, hyperphosphatemia
Vit D intoxication:
what are sx of Vit D intoxication?
weakness, HA somnolence N/V dry mouth constipation myalgia arthralgia metallic taste anorexia abdominal pain
suppurative thyroiditis
rare, non viral condition caused by gram (+) bacteria
what is the most common cause of suppurative thyroiditits?
Staph aureus
what are some clinical findings of suppurative thyroiditis?
tender thyroid gland, fever, pharyngitis, and overlying erythema along with leukocytosis and elvated ESR
how to dx suppurative thyroditis?
fine-needle aspiration w/ gram stain and culture
tx of suppurative thyroiditis
meds for underlying cuase and surgical drainage w/ fluctuation
what is subacute thyroiditis?
de Quervain’s, granulomatous, or giant cell
clinical features of de Quervain’s thyroiditis?
most common cause of a painful thyroid gland
peaks in summer
most commonly affects young and middle age women
what may precipitate DQ thyroiditis?
coxsackievirus, EBV, mumps, measles, adenovirus, echovirus, influenza
signs and symptoms of de quervians thyroditis?
tenderness, feer fatigue, dysphagia, otalgia
can persist for months
thyrotoxicosis initally presents–> followed by a perod of hypothyroidism w/ resumption of euthyroid
lab studies of DQ Thyroditis?
ESR elevated and antithyroid antibody titers are low
what is the treatment of DQ thyroditis?
ASA
BB, iodinated contrast products
what drug can induce thyroiditis?
amiodarone!
100 day half-life, 37% iodine by weight, (75 mg of iodine)
causes dysregulation in up to 20% of pts
what are the lab studies of drug induced thyroiditis?
incrase in T4 by 20-40% w.in the fisrt month, but can cause cellular resistance to t4 that leads to hypothyroid pci w/ elevated TSH and sx typical of hypothyroidism
what is chronic lymphocytic thyroiditis?
aka hashimoto
6X more common in F than M
-resin in prevalance over the past 50 years and mayb e related to increased iodine content in the NA merican diet
what is the most common thyroid dz in the US?
Hashimoto
what si the most common cause of sporadic goiter in kids?
hashimoto
what is the clinical feartures of hasimoto?
thyroid is diffusely enlarged w/ firm, small nodules and it often progresses to hypothyroidims w/ detectable thyrotropin receptor-blocking anibodys and antithyroid peroxidase
what is Fibrous thryroiditis?
rarest form- Riedel. development of dense fibrous tissue in the thyroid gland
-woody thyrroid
what else is seen w/ fibrous thyroiditis?
extraglandular fibrous involvemnt such as sclerosing cholangitis, retroperitoneal fibrosis, and orbital psuedotumor
dx of fibrous thyroiditis?
need bx bc needs to be differentiated w/ carcinoma
tx of fibrous thyroiditis?
tamoxifen
