Musculoskeletal Path Flashcards Preview

Renal/Skeletal > Musculoskeletal Path > Flashcards

Flashcards in Musculoskeletal Path Deck (111)
Loading flashcards...
1

A 78 year old woman comes to her physician due to new onset continuous back pain. She is diagnosed with a vertebral fracture and the following is seen on her x-ray. What is her diagnosis- what caused this injury?

Osteoporosis:
Primary= more common
1. Type 1= post-menopausal; absolute increase in osteoclast activity due to estrogen withdrawal
2. Type 2= > 70 years, attenuated osteoblast function (no increase in osteoclast activity)

Secondary osteoporosis: Associated with other conditions:
- Endocrine (Cushing's, hyperthyroidism, hypogonadism, iatrogenic steroids--> inhibited osteoblasts)
- Hematologic malignancies (Multiple myeloma--> activates osteoclasts
- Malabsorption (decreased Ca, Ph, Vit D)
- Alcoholism--> directly inhibits osteoblasts

 

2

A 58 year old man comes to his physician with increasing pain in his knees that worsens with activity. Suspecting arthritis, the physician orders an x-ray that reveals unusually dense bones. Additionally the man has had anemia refractory to iron supplementation. Based on these two clinical features, what is his possible diagnosis and treatment? What caused this pathology?

Osteopetrosis:
Marble bone disease: Albers-Schonberg disease
- Group of rare, heritable disorders; increased skeletal mass due to abnormally dense bone

Short, block-like radiodense bones on x-ray/CT
- Radiopaque, 2-3 times normal weight
- WEAK bone due to disorganized structure (can't remodel with stress)
- Calcified cartilage= weak, friable

Anemia due to replacement of marrow by sheets of osteoclasts, marrow fibrosis
- Extramedullary hematopoeisis
- Pancytopenia

Blindness, deafness (foramen entraps nerves)

Treatment: bone marrow transplant, human IFN-gamma

Types:
1.
Autosomal recessive= severe, fatal to infants
- Marked anemia, cranial nerve entrapment, hydrocephalus, infection

2. Autosomal dominant= mild anemia/ asymptomatic

Pathogenesis:
- Failed osteoclastic bone resorption
- Mutation in osteoclast formation/function genes
- Defect in acidification of bone
- Mutations: TCIRG1 (AD- proton pump); CLCN7 (AR- Chloride channel), Carbonic anhydrase II (AR); transciption factors, cytokines causing osteoclast differentiation
- Primary spongiosum remains--> cartilage cores, thickened cortex, lack of funnelization of metaphysis

 

3

A 35 year old man with a 15 year history of Ulcerative Colitis fractures his arm after falling in a soccer game. The x-ray of his arm reveals decreased bone density. What is his diagnosis and what caused this?

Osteomalacia:
Inadequate bone mineralization of newly formed bone, cartilage matrix
- Adults and kids--> osteopenia

Causes:
- abnormal Vit D metabolism
- Intestinal malabsorption

- Renal disorders
- Phosphate deficiency
- mineralization defects

Path:
- pseudofractures
- Exaggerated osteoid seams (osteoclast activity can't occur, delayed calcification)

 

4

A 65 year old woman comes to her physician complaining of pain in her head and light headedness as well as arthritis. Her physician is concerned she may have migraines but on DXA scan she has extremely low bone density. X-ray reveals abnormal bone formation. Based on her clinical symptoms and her x-ray, what is her diagnosis and what other diseases could she develop?

Paget's disease:
Pain (focal feature)
- Skull involvement (frontal/parietal)
- Pagetic steal--> light headedness (calvareal bone is stealing blood supply)
- Fractures/ arthritis
- High output cardiac failure (significant part of skeleton involved--> increased cardiac demands)
- Sarcomatous change, osteosarcoma in older patients (< 1%)

Chronic condition: bone enlargement and lytic lesions (disordered remodeling)
- uncoupling osteoblast/osteoclast activity
- See clast only activity, or blastic activity with patchy clast activity--> mosaic bone
- Seen in M & F > 60 years (3-4% in certain populations)
- Solitary or multiple sites

Pathogenesis: hereditary AD (chr 18)
- Sequestosome 1--> p62 protein in RANK pathway (more aggressive form)
- Viral nuclear inclusions similar to SSE (subacute sclerosing encephalitis)- giant cell tumor of bone

Path:
- "Hot" osteoclastic stage= lytic
- Mixed stage
- "cold" burnout stage: little activity

Histo:
- Prominent cement lines ("mosaic")
- Osteoclast= pathologic cell; "killer clasts" with 50+ nuclei (vs normal 8)

- Can see sarcomatous change in < 1% (adult type of osteosarcoma)

 

5

A 68 year old woman with multiple recent fractures is at the orthopedist's office for further evaluation of her condition. On x-ray there is a lesion in her bone that looks suspiciously different from her previous diagnosis of osteoporosis. A bone biopsy reveals atypia and hypercellularity. What is her diagnosis and what caused this?

Osteosarcoma due to Paget's disease: sarcoma formation:
Pain (focal feature)
- Skull involvement (frontal/parietal)
- Pagetic steal--> light headedness (calvareal bone is stealing blood supply)
- Fractures/ arthritis
- High output cardiac failure (significant part of skeleton involved--> increased cardiac demands)
- Sarcomatous change, osteosarcoma in older patients (< 1%)

Chronic condition: bone enlargement and lytic lesions (disordered remodeling)
- uncoupling osteoblast/osteoclast activity
- See clast only activity, or blastic activity with patchy clast activity--> mosaic bone
- Seen in M & F > 60 years (3-4% in certain populations)
- Solitary or multiple sites

Pathogenesis: hereditary AD (chr 18)

 

6

A 35 year old Asian woman presents with a fracture in her arm with no previous trauma. An x-ray reveals a lobulated, lytic lesion. Bone biopsy reveals the following cell type. What is her diagnosis and treatment?

Giant cell tumor:
Locally aggressive
-20s-40s F > M, Asians
- Site: epiphysis, metaphysis of long bones

Clinical: pain, path fractures

X-ray: lytic, multilobulated "soap bubble"

Gross: Blood-filled sponge

Histo: mononuclear spindle-shaped cells and mononucleated giant cell tumors

Treatment: curettage, recur (50%), 10-15% lung mets

 

7

Osteochondroma

Developmental defect (hamartoma) at epiphyseal plate
- "Ring of Ranvier"
- Cartilage capped growth growing away from joint

Hereditary multiple osteochondromatosis:
- Extra genes on Chromosomes 8, 11, 19--> chondrocyte proliferation and differentiation

8

A 15 year old boy is brought to his family physician due to increasing pain in his hip. An x-ray revels a lytic lesion in the head of his femur. Additionally his alkaline phosphatase levels are elevated on a blood panel. He is sent to a surgeon to have the head of the femur replaced. Based on the specimen and the woven bone with atypical osteoblasts found within, what is his diagnosis?

Osteosarcoma

Most common PRIMARY malignant bone-forming tumor (most common bone tumor= metastatic)
- 2nd decade, M > F
- Rb gene mutation in 2/3; p53

Sites: metaphysis of femur, tibia > humerus

X-ray: lytic, sunburst pattern, codman's triangle

Clinical: Pain, increased alk phos

Histo: woven bone (osteoid) with malignant osteoblasts

Variants:
- Parosteal
- Periosteal
- Telangiectatic

9

A 15 year old boy presents with pain and swelling in his femur. A bone biopsy revelas the following small round blue cells that stain positive for CD99 and PAS. What is his diagnosis and treatment?

Ewing sarcoma:
Uncommon
- 2/3 < 20 years, M > F (2:1)
- Reciprocal translocation t(11;22)(p13;q12), PNET family

Clinical: pain, swelling

X-ray: midshaft/diaphysis of long bones; "onion skin pattern"

Histo: small round blue cell tumor
- PAS, CD99
- t(11;22) or t(21;22)

Treatment:
- Chemo/radiation
- surgery
- 60-75% 5-year recurrence rate

 

10

A 15 year old boy presents with pain and swelling in his femur. A bone biopsy revelas the following small round blue cells that stain positive for CD99 and PAS. What is his diagnosis and treatment?

Ewing sarcoma:
Uncommon
- 2/3 < 20 years, M > F (2:1)
- Reciprocal translocation t(11;22)(p13;q12), PNET family

Clinical: pain, swelling

X-ray: midshaft/diaphysis of long bones; "onion skin pattern"

Histo: small round blue cell tumor
- PAS, CD99
- t(11;22) or t(21;22)

Treatment:
- Chemo/radiation
- surgery
- 60-75% 5-year recurrence rate

11

A 42 year old man is treated by his physician for pain in his hip. A CT-scan reveals a lesion in his pelvic bone with calcification and lytic lesions. Histological samples reveal the following. What is his diagnosis?

Chondrosarcoma:
2nd most common primary malignant bone tumor
- M > F, 4th-6th decade
- Some from cartilage enchondromas
- Variants classified by location
- Can see molecular trisomy 7, rearrangement of chrom 17
* extracellular sarcoma mixoid type: (9;22)(q31;q12)

Sites:
- Axial, proximal femur, humerus

X-ray: lucent or ring-like; calcified and lytic areas

Histo: grading based on cellularity, degree of atypia

 

12

A 77 year old woman visits an orthopedist due to recurrent, worsening knee pain that now restricts her daily activities of living. Based on the imaging below, what is her diagnosis?

Primary osteoarthritis:
Most common form of joint disease
- Slow, progressive
- Seen in articular cartilage of weight bearing joints, fingers
- Older patients (or young following trauma)

1. Primary osteoarthritis:
Unknown etiology; several postulated factors:
- increases with age
- 85% of patients age 75-79
- < 45 years= male predominant; > 55 years= females
- Hereditary factors?

2. Secondary osteoarthritis:
Known etiology

Clinical:
See joint space narrowing, subchondral bone thickening, painful joint
- Pain follows activity
- Restriction of motion
- Lab findings unhelpful
- Supportive therapy

Pathology:
- Seen at DIP, PIP of upper extremity; knees, hips, cervical and lumbar spin
- Narrowing of joint space on x-ray
- Increased subcondral bone, bone cysts
- Osteophyte formation

Histology:
- Earliest= death of articular cartilage
- Cracking, fibrillation
- Reactive bone/cartilage--> fibrocartilage plug
- Eburnation (loss of articular cartilage- BELOW), subchondral bone cyst (decreased density on x-ray), osteophyte (dense bone formation with cartilage cap, continuous marrow)

 

13

A 77 year old woman visits an orthopedist due to recurrent, worsening knee pain that now restricts her daily activities of living. Based on the gross specimen below, what is her diagnosis?

Primary osteoarthritis subchondrial cyst:
Most common form of joint disease
- Slow, progressive
- Seen in articular cartilage of weight bearing joints, fingers
- Older patients (or young following trauma)

1. Primary osteoarthritis:
Unknown etiology; several postulated factors:
- increases with age
- 85% of patients age 75-79
- < 45 years= male predominant; > 55 years= females
- Hereditary factors?

2. Secondary osteoarthritis:
Known etiology

Clinical:
See joint space narrowing, subchondral bone thickening, painful joint
- Pain follows activity
- Restriction of motion
- Lab findings unhelpful
- Supportive therapy

Pathology:
- Seen at DIP, PIP of upper extremity; knees, hips, cervical and lumbar spin
- Narrowing of joint space on x-ray
- Increased subcondral bone, bone cysts
- Osteophyte formation

Histology:
- Earliest= death of articular cartilage
- Cracking, fibrillation
- Reactive bone/cartilage--> fibrocartilage plug
- Eburnation (loss of articular cartilage), subchondral bone cyst (decreased density on x-ray), osteophyte (dense bone formation with cartilage cap, continuous marrow)


 

14

A 77 year old woman visits an orthopedist due to recurrent, worsening knee pain that now restricts her daily activities of living. Based on the histologic sample below, what is her diagnosis?

Primary osteoarthritis: osteophyte:
Most common form of joint disease
- Slow, progressive
- Seen in articular cartilage of weight bearing joints, fingers
- Older patients (or young following trauma)

1. Primary osteoarthritis:
Unknown etiology; several postulated factors:
- increases with age
- 85% of patients age 75-79
- < 45 years= male predominant; > 55 years= females
- Hereditary factors?

2. Secondary osteoarthritis:
Known etiology

Clinical:
See joint space narrowing, subchondral bone thickening, painful joint
- Pain follows activity
- Restriction of motion
- Lab findings unhelpful
- Supportive therapy

Pathology:
- Seen at DIP, PIP of upper extremity; knees, hips, cervical and lumbar spin
- Narrowing of joint space on x-ray
- Increased subcondral bone, bone cysts
- Osteophyte formation

 

15

A 50 year old man with a 20-year history of rheumatoid arthritis comes to the emergency room with a painful swelling in his calf (below). Based on his condition, what could possible be occuring and what is he as risk for?

Rheumatoid arthritis of the knee: Ruptured Baker's cyst
Clinical presentation:
Bilateral, symmetrical
Large and small joints
Inflammation of the synovium
Fluid accumulation in the joint
Joint swelling and pain
If not diagnosed and treated vigorously--> destruction, deformity, disability

Knee
- Synovitis causing Baker’s cyst (rupture-DVT)

Epidemiology:
Relatively common disorder
- Affects >1% of the population of North America
- Female:male  2.5:1
- Incidence increases with age (Peak: 4th-6th decade)

Associated with shortened life expectancy
Constitutional symptoms: LGF, wt loss, anorexia, fatigue
Extra-articular involvement:
- Lungs, skin, heart, hematologic, eye, vessels
- Rarely: CNS (rheumatoid nodules), kidneys
- Differentiate from drug side effect!

16

A 30 year old woman presents to her physician with worsening joint pain over the last 6 months, especially in her knees. She noticed some pain and swelling in her hands but thought it was related to her work in a dressmaker's shop, but now her knees are hurting as well. Based on gross specimens below, what types of changes are occuring and what is her possible diagnosis?

Rheumatoid arthritis: Articular cartilage destruction from periphery of joint (central sparing

Below: Papillary synovial hyperplasia, subsynovial lymphoplasmacytic infiltration

Pathophys:
- Overactive T cells--> attack synovial fluid space--> Synovial inflammation:
- Fluid filled with neutrophils
- Pannus infiltrated by T lymph, macrophages, fibroblasts, plasma cells, endothelial dendritic cells
--> chronic inflammation
---> Bone, cartilage, ligament, tendon damage
--> erosions, joint deformity

Treatment:
Goal is complete remission
1. Start with anti-inflammatory medications
- NSAIDs
- Corticosteroids
2. Add immunomodulators (DMARDs) early
3. If no significant improvement in first few months add “biologics”
- Antibodies against inflammatory cytokines

17

A 45 year old woman with a 20 year history of rheumatoid arthritis comes to the emergency room with the following necrosis in her fingertips. Additionally she has a marked footdrop. What is occuring and what is her treatment?

RA vasculitis: extremity and nerve involvement:
Overactive T-lymphocytes infiltrating and destroying capillary structures supplying fingertips, nerves
Vasculitis
- Arterioles, capillaries, venules
- Mostly leukocytoclastic vasculitis
- Skin ulcerations (necrotizing)

Nervous system:
1. Myelopathy
2. Mononeuritis multiplex:
- disorder characterized by simultaneous or sequential damage to more than one nerve group
- isolated damage to at least 2 separate nerve areas
- involves destruction of the axon
- interferes with nerve conduction at the location of the damage (see wrist, foot drop)

- causes include a lack of oxygen caused by decreased blood flow or inflammation of blood vessels. No cause is identified for about one-third of cases

Treatment:
Goal is complete remission
1. Start with anti-inflammatory medications
- NSAIDs
- Corticosteroids
2. Add immunomodulators (DMARDs) early
3. If no significant improvement in first few months add “biologics”
- Antibodies against inflammatory cytokines

 

18

A 65 year old woman with a 40-year history of rheumatoid arthritis presents to her physician with the followin in her eye. What has occured? Additionally, she has been having increasing difficulty breathing. What might be causing her breathing problems?

Rheumatoid arthritis: extra-articular manifestations:

Front: Ocular
- Keratoconjunctivitis sicca (also seen in Sjogren's)
- Episcleritis (more superficial than scleritis)
- Scleritis
- Scleromalacia perforans (rheumatoid nodule)
Below:
Pulmonary
- Pleural disease
- Interstitial lung disease
- Pulmonary nodules

19

Below is a histological specimen from the PIP joint of a 40 year old woman with a history of RA. What is present in her joint that is abnormal and how might it be contributing to her symptoms?

Rheumatoid Arthritis: Pannus:
Granulation tissue formation over joint space (arthritis) or over cornea, etc.
Pathophys:
- Synovial inflammation:
- Fluid filled with neutrophils
- Pannus infiltrated by T lymph, macrophages, fibroblasts, plasma cells, endothelial dendritic cells
- Leads to articular cartilage and juxta-articular bone loss
 

Front: Pannus overlying articular cartilage
Back: hyperplastic synovium of pannus

20

A 50 year old woman with a 30 year history of rheumatoid arthritis presents to her physician after noticing a nodule on her elbow that is giving her some pain. The nodule is biopsied and the following is found. What is it and why did it form?

RA nodule (extra-articular):
Subcutaneous nodules at areas of pressure (skin on elbows, legs)
- Moveable, firm, rubbery, occasionally tender

Front: rheumatoid nodule with central fibrinoid necrosis
Below: Palisaded macrophages surrounding rheumatoid nodule

21

The same 45 year-old caucasian female also complains that she has to drink water more frequently, not because she is thirsty, but because she is unable to swallow food or speak properly without doing so. Exam of her tongue revelas the following. What other oral manifestations would be seen in Sjogren's?

Sjogren's: oral involvement:
Dry mouth (xerostomia)--> decreased saliva
- Difficulty swalling food, inability to speak, change in taste, burning sensation, increased in dental caries
- Physical exam: dry, erythematous, sticky oral mucosa, dental caries, scanty/cloudy saliva, angular chelitis
- Parotid, major salivary gland enlargement in 60% patients (episodic or chronic, unilateral--> bilateral)

Complications:
- accelerated caries, loss of dentition, poor fitting dentures,
- oral candidiasis (yeast infection with Candida albicans),
- sialolithiasis (salivary gland stones),
- sialostenosis (salivary gland strictures),
- bacterial sialadenitis (infection),
- disturbed sleep (related to nocturnal fluid ingestion),
- depression and weight loss (related to oral discomfort, dysphagia etc.).

Diagnostic questions:
1. Symptoms of dry mouth for at least 3 months?
2. Recurrent or persistently swollen salivary glands?
3. Need for liquids to swallow dry foods?

Objective documentation of dry mouth
- Oral examination: diminished salivary pool, loss of glistening of tongue, mucous membranes, erythema, fissures on tongue
- Sialometry: Measure salivary flow using Lashley cup; circular cup connected to plastic tube, collect parotid saliva (placed over Stensen's duct)- normal resting = 0.1 ml/min, after citric acid = 0.5-1.5 ml/min
- Salivary scintigraphy: nuclear medicine test to measure isotope uptake into glands (saliva formation) plus stimulated salivary discharge
- Sialography: inject contrast medium into salivary ducts followed by routine x-rays (MRI)

Confirmation of histologic involvement by salivary gland biopsy (below)
- Labial minor salivary gland biopsy on inner aspect of lip
- Findings: focal lymphocytic sialadenitis= accumulation of 50+ mononuclear cells around salivary gland acini, ducts
1. Divide number of foci by glandular surface area= focus score
2. Focus score > 1/4 mm3= Sjogren's

22

A 45-year old caucasian female comes to her physician complaining of persistant dry eyes. On exam it is noted that her eyes appear red and there is destruction of the conjunctival epithelium. What other tests can be done to test for pathological dry eyes and what other symptoms would indicate Sjogren's Syndrome?

Sjogren's keratoconjunctivitis, dry eye:
Chronic inflammation of lacrimal glands:
- produce decrease in tear production
- Diminished tear production leads to the destruction of both corneal and conjunctival epithelium and a constellation of clinical findings termed keratoconjunctivitis sicca (KCS).

Physical signs:
- Dilation of the conjunctival vessels, pericorneal injection, (red eye)
- Irregularity of the corneal image and
lacrimal gland enlargement.
- The patient usually complains of a burning, sandy or scratchy sensation under the lids, itchiness, redness and photosensitivity.
- Failure to treat dry eyes may result in complications such as corneal ulcers or melting, corneal perforation, loss of vision, bacterial conjunctivitis or blepharitis (inflammation of the eyelids).

Diagnostic questions:
1. Symptoms of dry eyes for at least 3 months?
2. A foreign body sensation in the eyes?
3. Use of artificial tears 3 or more times per day?

Objective documentation of dry eyes
- Schirmer's test (below): measures tear production on strip of paper in eye duct (normal > 10mm/5 min)
- Rose Bengal/ fluorescien corneal staining: ocular surface irregularity or damage due to dryness
- Tear break film test: tear film stability between last blink and appearance of dark, non-fluorescent areas in tear film (normal > 10 seconds)

Diagnosis of Sjogren's syndrome:
1. Dry mouth: documentation
2. Dry eyes (document via above tests)
3. Autoantibody presence:
- Positive ANA, Rheumatoid Factor (> 1:160)
- Positive anti-SSA (Ro) or anti-SSB (La)
4. Salivary gland biopsy for histologic involvement

23

A 40 year old obese man comes to his physician because he developed a recent onset of excruciating pain in his left big toe (below). This has never happened to him before and there was no trauma to his foot. What might his diagnosis be and how would this be confirmed?

Acute gouty attack:
Acute attack
- Abrupt, monoarticular
- Involves MTP --> ankle, tarsal joint, knee, wrist, elbow
- Exquisite tenderness, swelling, warmth
- Fever, leukocytosis may occur
- Overlying skin desquamates
- Lasts 3-10 days w/o treatment

Precipitating event of acute attack:
- Trauma, surgery, stress, infection, food (red meat, shellfish), alcohol (beer)
- Diuretics, low dose aspirin

 

Diagnosis of Gout: Urate crystals:
- Crystal in the aspirate:
- Monosodium urate monohydrate= needle shaped
- Differentiate from calcium pyrophosphate dihydrate (pseudo-gout)- NOT needle shaped
- Crystal aligned with polarizer= yellow
- Perpendicular to polarizer= blue
- Negative birefringence (vs CPP= positive birefringence)
- Crystal inside neutrophils= acute gout attack

24

A 60 year old man with a history of recurrent gout comes to his physician who notes the following on his ear. What is this a symptom of and how is the diagnosis confirmed?

Chronic Gout tophi: deposition of urate crystals (below)

Acute arthritis; inflammatory response to MSU (urate) crystals in joints
- Generally starts in 1st MTP joint (big toe)
- Peripheral joints, tendons, any tissue
- Recurent
- Chronic, deforming
- Males/post-menopausal women
- Associated with Lesch-Nyhan syndrome: mutations in the HPRT gene located on X chromosome--> HGPRT enzyme defect--> uric acid buildup

Pathophys:
- Sodium urate triggers immediate immune response (potent trigger)
- Leads to production of IL-1--> inflammatory cascade
- Cells move to site of urate deposition
- Cannot remove urate
- Eventually immune response tapers

Clinical presentation of Chronic gout (tophaceous gout):
Result of:
- Years of persistent hyperuricemia
- Frequent attacks
- Inadequate therapy

Features of chronic gout:
- Joint destruction
- Tophi: subcutaneous tissue, tendons, IP-MCP joints, pinna of ear
- Extra-articular: myocardium, pericardium, aortic valves, extra-dural spinal, kidneys
- May mimic RA but less symmetrical

 

25

A 35 year woman comes to her physician after vacationing with her family because she developed a horrible rash on her face and neck. What is possible cause of the rash and how frequently is this the first manifestation of this disease?

SLE: cutaneous manifestations

Front: photosensitivity rash (both cutaneous and overall ill-feeling when exposed to sunlight)
Below: Malar rash: Fixed erythema, flat or raised, sparing the nasolabial folds

SLE: primary manifestations:
1. Arthritis (55%)
2. Skin involvement (25%)
3. Nephritis (5%)
4. Fever (5%)
5. Other (15%)

26

What is the phenomenon noted below in a patient diagnosed with systemic lupus? What is the epidemiology of her disease?

SLE- Jaccoud's arthropathy:

Early onset: Finger alignment appears abnormal but can be manipulated back into normal position
Later onset: permanent deformity

- Incidence of 1.8 to 35 cases per 100,000/ year in general population
- Prevalence fluctauates from 250000 to 1.5 million cases of lupus.
- Women>Men – 9:1 ratio
- African Americans>Hispanics>Whites
- Usual onset between 15-45 years (60% cases)

27

Below is a patient being seen for Systemic lupus. What type of deformity is apparent and what caused these changes?

SLE: discoid rash: Raised patches, adherent keratotic scaling, follicular plugging; older lesions may cause scarring

Etiology is unknown
• SLE is an autoimmune disease
• Genetic factors
– HLA association (HLA DR2/HLA DR3)
• Environment factors
– Sunlight, drugs, chemicals, foods
– Bacterial or viral infections
– More associated with flares and exacerbations
• Hormonal factors
– Increased estrogen and prolactin levels
- Flares during pregnancy (vs RA)

Immune changes:
- Abnormal complement components (C1q, C4, etc )
- Fc Receptor abnormalities
--> delay in clearing dying (apoptotic) cells, exposing more autoantigens.

 

28

A 16 year old girl with SLE is brought to her physician because of a new onset of rash and papules in her mouth. Her mother is worried about the progression of her daughter's condition and wants to know what other manifestations may occur. What might happen in a lifetime of SLE?

SLE: bullous lesions
Joints 90%:
- Arthritis and/or artharlgias are the most common presenting manifestation of SLE
- Most cases: Symmetrical.
- Unlike RA, is usually non-erosive ( at xrays) w/ subluxations, initially reversible.
- Involve periarticular surfaces.
- Increase frequency of tendon rupture.
- Fibromyalgia can overlap joint sx.

Skin
- Rashes 70%: butterfly rash, interarticular dermatitis, palpable purpura
- Discoid Lesions 30%: erythematous, hyperpigmented; flattened; scarred central areas with thin/fragile epidermis; follicular plugging
** Discoid lupus can become systemic lupus
- Alopecia: diffuse 40%

Pleuropericardium 60%
- Serositis: pleuritic pain more frequent than effusions
- Fluid exudative with normal glucose

Pulmonary manifestations:
- Pneumonitis
- Pulmonary hemorrhage (small capillary leak)
- PAH
- Shrinking lung syndrome (diaphragm, respiratory muscles)

Cardiac manifestations:
- Most common cause of mortality in SLE is CAD
- Endocarditis in 15-60% (asymptomatic)= Libman-Sacks endocarditis
- Myocarditis in 9%: mild, seen as diastolic dysfunction
- Clots in placental tissue--> miscarriages

Kidney 50%
Raynaud’s 20%
Mucous Membranes 15%
CNS (Seizures/Psychosis) 15%

 

29

A 50 year old woman has been suffering from SLE for 20 years and comes into her physician with increasing problems breathing. An MRI reveals the following. What is occuring with her lungs?

SLE: pulmonary manifestations
"Shrinking lung syndrome"
Pulmonary manifestations of SLE:
- Pneumonitis
- Pulmonary hemorrhage (small capillary leak)
- PAH
- Shrinking lung syndrome (diaphragm, respiratory muscles)

30

A 45 year old man with a 20-year diagnosis of SLE comes to his physician for a physical. His urine sample reveals elevated protein levels. Based on the histology below, what is his diagnosis and what types of changes are seen in kidneys in patients suffering from lupus?

SLE: lupus nephritis
Class I: Normal glomeruli
a) Nil by all techniques
b) Normal by light but deposits on EM or IF

Class II: Mesangial glomerulonephritis: mesangial cells affected

Class III: Focal glomerulonephritis: endothelial cells affected

Class IV: Diffuse glomerulonephritis: endothelial cells affected

Class V: Diffuse membranous glomerulonephritis: epithelial cells affected

Class VI: Advanced sclerosing glomerulonephritis

Lupus nephritis:
Anti-DNA Antibody deposition, complement activation will produce inflammation, occlusion and disruption of glomeruli that translate in:
- Protein urinary excretion (Nephrotic Sd)
- Hematuria (Nephritic Sd)
- Increase on Creatinine levels
- Renal Failure