Diseases of Bone - Systemic Diseases

Question 1

describe Gardner syndrome

Answer 1

• autosomal dominant many cases are new mutations
• intestinal polyposis with 100% malignant transformation
• osteomas and jaw bone densities
• supernumerary teeth

Question 2

what are the other names for osteogenesis imperfects

Answer 2

• brittle bone disease
• lobstein disease

Question 3

describe osteogenesis imperfects

Answer 3

• a group of diseases involving defective synthesis of type I collagen, the most widely distributed collagen in the body ( bone, joints, eye, teeth)
• the skeletal manifestations consisting of extreme bone fragility, are the most prominent clinical findings

Question 4

four types of osteogenesis imperfecta may be inherited in an:

Answer 4

autosomal dominant or recessive manner

Question 5

what are the features seen in osteogenesis imperfecta

Answer 5

• too little bone
• cortical thinning
• attenuated trabeculae
• skeletal fragility, deformity, short stature
• blue sclera
• joint laxity
• dentinogenesis imperfecta

Question 6

what is the differential diagnosis of the battered child syndrome

Answer 6

evidence of multiple fractures raises the suspicion of possible child abuse

Question 7

what is the pharmacologic treatment for osteogenesis imperfecta

Answer 7

bisphosphonates

Question 8

what are the other names for osteopetrosis

Answer 8

• marble bone disease
• albers schonberg disease

Question 9

describe osteopetrosis

Answer 9

• a group of rare genetic diseases in which bone density is increasde
• reduced osteoclast bone resorption resulting in diffuse, symmetric skeletal sclerosis
• progressive obliteration of the marrow cavity

Question 10

describe osteoclast dysfunction in osteopetrosis

Answer 10

• osteoclasts are multinucleated cells located in resorption pits (howship lacunae)
• osteocalsts acidify the local environments to dissolve mineral and release enzymes to degrade bone matrix proteins
• enzyme defects interfere with acidification of the resorption put and prevent bone removal

Question 11

continued osteoblastic apposition in the absence of osteoclastic resorption leads to:

Answer 11

increased density of both cortical and cancellous bone

Question 12

what are the forms of osteopetrosis

Answer 12

• autosomal recessive infantile malignant osteopetrosis - most severe- becomes evident in utero or soon after birth
• autosomal dominant adult benign osteopetrosis - least severe and may not present until adulthood

Question 13

what are the complications of osteopetrosis

Answer 13

• dense but abnormally brittle bones that fracture easily
• bone marrow failure: neutropenia, normocytic anemia, extramedullary hematopoiesis
• narrowing of scull foramina: blindness, deafness, facial nerve paralysis, impaired venous drainage
• jawbones: delayed tooth eruption, osteomyelitis

Question 14

describe paget disease of bone

Answer 14

• excessive and abnormal remodeling of bone caused by osteoclast dysfunction
• possibility of a viral infection by a slow virus or paramyxovirus, measles virus or respiratory syncytial virus
• a focal, localized process that may present as a solitary lesion (monostotic) or may occur at multiple sites (polyostotic) with marked variation at each location

Question 15

what is another name for paget disease of bone

Answer 15

osteitis deformans

Question 16

what is the mutation in paget disease of bone

Answer 16

osteoclast activation via NF-kB transcription signaling pathway

Question 17

what are the stages of paget disease of bone

Answer 17

• initial lytic stage
• mixed lytic sclerotic stage
• late sclerotic stage

Question 18

who is affected by paget disease of bone

Answer 18

• older individuals- affects 3% of population over 40 in some countries - geographic variation

Question 19

paget disease of bone produces:

Answer 19

enlargement of affected bones, impinging on cranial foramina

Question 20

what are the types of paget disease of bone

Answer 20

monostotic or polystotic

Question 21

what are the features of paget disease of bone

Answer 21

• pain, headache, deafness, visual disturbances
• change in hate size, denture fit

Question 22

what is the radiographic presentation of each stage of paget disease of bone

Answer 22

• vascular phase- lucency
• sclerotic phase- increased opacity, cotton wool bone
• generalized hypercementosis

Question 23

what are the biochemical features of paget disease of bone

Answer 23

• increased: serum-bone specific alkaline phosphatase, total serum alkaline phosphatase, urinary hydroxyproline, N-telopeptidase, C-telopeptides, pridinoline cross link assay
• normal: serum phosphate, serum calcium

Question 24

what are the complications of paget disease of bone

Answer 24

• bowing, deformity, pathologic fracture
• high output cardiac failure in vascular phase
• infection in sclerotis phase
• bone neoplasia

Question 25

describe the bone neoplasia in paget disease of bone

Answer 25

• pagetic bone exhibits higher incidence of benign and malignant neoplasms
• osteosarcoma is the most common sarcoma complicating Paget disease

Question 26

what is the treatment and prognosis of paget disease of bone

Answer 26

• pharmacologic- bisphosphonates, calcitonin
• in the absence of malignant transformation, usually not a serious or life threatening disease

Question 27

what is the histo presentation of paget disease of bone

Answer 27

• reversal lines
• mosaic, jigsaw pattern