KUSHAGRA, MS IV, MAMC, DELHI DR. GILLIAN LIEBERMAN, M.D. AUGUST 23, 2010
Definition Epidemiology Pathophysiology, Etiology and Risk Factors Stages and Clinical Features Associated Co-Morbidities Common Sites and Distribution Patient Discussion Classical Findings Differential Diagnosis Menu of Imaging Studies Management and Preventive Measures
GOUT is a form of peripheral arthritis resulting from the deposition of monosodium urate crystals secondary to hyperuricemia. The metatarsal- phalangeal joint at the base of the big toe is the most common affected.( Also known as PODAGRA). emedicine.medscape.com
Gout is a common systemic metabolic disease, affecting more than 1% of the population. It is the most common inflammatory arthritis, afflicting 1 or more joints in men older than 40 years of age. Typically occurs in middle aged or elderly males (90% of cases are in males). Prevalence in the United States: 1.6 to 13.6 per 1000.
Gout can be broadly classified into 2 types: PRIMARY SECONDARY Gout is called Primary when no identifiable disease causing the hyperuricemia can be found. Primary Gout occurs in Majority of the cases. Secondary Gout, which is less common, occurs due to some underlying disease.
Causes can be broadly classified into : INCREASED URIC ACID PRODUCTION (5%-10% of patients) DECREASED URIC ACID EXCRETION (90%-100% of patients)
INCREASED URIC ACID PRODUCTION (5%-10% of patients) Genetic enzymatic defects Hypoxanthine-guanine phosphoribosyl transferase deficiency glucose-6-phosphatase deficiency 5-phosphoribosyl-1-pyrophosphate synthetase overactivity
INCREASED URIC ACID PRODUCTION (5%-10% of patients) Acquired causes Dietary indiscretions: excessive purine diet Obesity Increased tissue turnover tumors, lympho-proliferative disorders Vigorous muscle exertion causing increased turnover of ATP Alcohol-induced turnover of ATP Chemotherapy
DECREASED URIC ACID EXCRETION (90%- 100% of patients) Genetic causes Down syndrome Polycystic kidney diseases Acquired causes Kushagra, MAMC MS IV Diminished renal function Inhibition of tubular urate secretion: competitive anions (keto-acidosis and lactic acidosis)
DECREASED URIC ACID EXCRETION (90%- 100% of patients) Acquired causes Enhanced tubular urate reabsorption: Dehydration Starvation Kushagra, MAMC MS IV Insulin resistance (metabolic syndrome) Medications: Low-dose aspirin Thiazide and diuretics Ethambutol Niacin Lead nephropathy
Humans do not express the enzyme urate oxidase (uricase), because of a mutation during evolution of the uricase gene, which converts urate to the more soluble and easily excreted compound allantoin. Less Soluble More Soluble
Among mammals, only humans and other primate species excrete uric acid as the end product of purine metabolism. Uric acid is a weak organic acid that exists mainly as the urate ion at ph >5.75 and as the un-ionized uric acid form at more acidic (lower) ph levels. Thus, the urate form predominates in all extracellular fluids, including serum, in which physiological ph is 7.4. In urine, which is usually acidic, the un-ionized uric acid form predominates.
When overproduction or underexcretion of uric acid occurs, the serum urate (SU) concentration may exceed the solubility of urate (a concentration approximately >6.8mg/dl), and supersaturation of urate in the serum (and other extracellular spaces results. This state, called hyperuricemia, imparts a risk of crystal deposition of urate in tissues from the supersaturated fluids.
1. ASYMPTOMATIC STAGE 2. ACUTE GOUTY ARTHRITIS 3. INTER-CRITICAL GOUT 4. CHRONIC TOPHACEOUS GOUT
ACUTE GOUTY ARTHRITIS 90% of attacks involve a single joint with severe pain, redness and swelling. Mostly involving the lower extremity, usually the first metatarsal-phalangeal joint.(>50%) beliefnet.com qwickstep.com
INTER-CRITICAL GOUT These are asymptomatic intervals between acute attacks most common early in disease progression. This pattern is quite uncommon in other arthritic disorders and alone is very suggestive of gout.
CHRONIC TOPHACEOUS GOUT The tophus is the pathognomonic lesion of gout and is essentially a foreign body granuloma. Seen in the external ear and pressure points over the elbows, hands, feet, knees, and forearms. hopkins-arthritis.org cedar-sinai.edu
PAIN Rapid onset and progression. Worst pain that the person has ever endured. Associated with warmth, redness, and swelling of the affected joint. Systemic symptoms and signs of fatigue, fever and chills may accompany. The first episode of gouty arthritis often begins at night.
GOUTY NEPHROPATHY Two renal syndromes are associated with hyperuricemia: acute urate nephropathy and uric acid urolithiasis.. kidney-stone-treatment.blogspot.com lithostat.com Uric acid stone Calcium oxalate stones
Patients also have an increased incidence of calcium oxalate stones because urate crystals serve as nidus for calcium stone formation. Isosthenuria (inability to concentrate urine), pyelonephritis and proteinuria are other renal manifestations.
BONE EROSIONS Deposits of urate crystals (tophi) form along the margins of the articular cortex and may erode the underlying bone, producing small, sharply marginated, punched-out defects at the joint margins of the small bones of the hand and foot. appliedradiology.com Frontal and Lateral view of the Index finger showing pressure erosion Large soft tissue mass associated On the volar surface of middle phalanx by soft tissue mass. With osteolysis of first MTP joint.
SOFT TISSUE ABNORMALITIES Tophi (Soft Lumpy Nodule) can be seen radiologically most commonly at: First metatarsophalangeal joint The ear Olecranon bursa and The Achilles tendon Ear Tophi wikipedia.org Tophi on Knee wikipedia.org
BONE MINERALISATION The bone mineral density is preserved until late in the disease. Extensive osteoporosis is not a feature of gout. The presence of normal mineralization may help differentiate this condition from rheumatoid arthritis. The reason for the presence of normal mineralization is that the duration of the attack is too short to allow the development of osteoporosis of disuse as is seen in rheumatoid arthritis.
CHONDROCALCINOSIS Five percent of patients with gout have cartilage calcification or chondrocalcinosis. Chondrocalcinosis manifests because they have a predisposition for calcium pyrophosphate dihydrate crystal deposition disease (CPPD). ARTICULAR ABNOMALITIES The joint space is well preserved until late in the course of the disease. The presence of relatively normal joint space and preservation of the articular cartilage with extensive erosions is a distinctive radiographic feature of gout. BURSITIS
CARDIOVASCULAR DISEASES: HYPERTENSION MYOCARDIAL INFARCTION STROKE METABOLIC SYNDROME OBESITY HYPERTENSION HYPERLIPIDEMIA INSULIN RESISTANCE
sedico.net
Lower extremity > upper extremity Small joints > large joints Random distribution in hands (helpful diagnostic distinction) First MTP most common (podagra) Asymmetric distribution is characteristic of gouty arthritis.
Joint Freque ncy DIP ++ 1st IP ++ 2nd-5th PIP ++ 1st MCP ++ 2nd-5th MCP ++ 1st CMC +++ 2-5 CMC +++ Midcarpal +++ Radiocarpal ++ gentili.net Radioulnar ++
81 year old lady came to the OPD with soft lumpy nodules over hands. She was having difficulty in extending fingers of the Right hand. She had episodes of pain, redness and swelling in the Right hand since past 10 years. The left hand got involved over a period of time. Denies any recent fever, fatigue or weight loss She is having nodules at the right elbow and 1 st MTP in both feet.
Extensively calcified tophi and bony destructive changes are seen involving the DIP and PIP joints of the 2nd, 3 rd and 4th digits. Erosions are seen at the base of the 1st metacarpal, head of the 2nd metacarpal and ulnar styloid process. PACS
Patient is unable to extend the fingers of her Right hand. Erosions are noted in the right hand at the head of the 5th metacarpal and base of the 1st metacarpal bones. PACS
Bony destruction with overhanging cortical edges are noted along the lateral condyle. Adjacent subchondral cysts and osseous fragments are noted within this region. PACS
Extensive destructive changes of all digits involving the MTP, PIP and DIP joints of the right feet are noted with extensively calcified large tophi. PACS
Tarsometatarsal and ankle joint tophi and bony destruction can be seen. Marked bony destruction can be noted on MTP, DIP and PIP. PACS
Extensive destructive changes of all digits involving the MTP, PIP and DIP joints of the left feet are noted with extensively calcified large tophi. There are medial subluxations of the 2nd and 3 rd metatarsal phalangeal joints of the left foot. PACS BIDMC
Tarsometatarsal and ankle joint tophi and bony destruction can be seen. PACS BIDMC Marked bony destruction can be noted on MTP, DIP and PIP.
Lateral radiograph of the elbow Amorphous calcified tophaceous deposits in the olecranon bursa. appliedradiology.com
Gout- Olecranon Bursitis. There is soft tissue swelling in the olecranon bursa (white arrow) a finding suggestive of gout. There are also erosions (blue arrows) around the elbow joint. learningradiology.com There is no periarticular demineralization.
Frontal view of the index finger Well-defined subarticular cyst in this patient who has gouty arthritis. appliedradiology.com
Frontal Radiograph of the foot Erosion with Typical overhanging edge at the head of the first metatarsal. appliedradiology.com
Lateral radiograph of the ankle Thickened Achilles tendon due to deposition of urate crystals. The integrity of the Achilles tendon is apparently maintained. appliedradiology.com
Xanthomatosis Kushagra, MAMC MS IV CPPD (Pseudo gout) Psoriasis Rheumatoid arthritis Amyloidosis Joint infection Osteoarthritis
GOUT Ratio of men to women 7:1 1:1.5 Age group affected Men >40 years old Postmenopausal women PSEUDOGOUT Elderly Serum urate Elevated Normal Joints involved First MTP joint, knees, wrists, fingers, olecranon bursa Involvement of 1st MTP Common Rare Knees, wrists, ankles Tophi Present Rare tophi-like deposits Radiographic findings Crystals Erosions with overhanging edges Needle-shaped, strong negative birefringence Chondrocalcinosis Rhomboid-shaped, weakly positive birefringence
PSORIASIS progressive joint-space destruction paravertebral ossification sacroiliac joint involvement RHEUMATOID ARTHRITIS presence of symmetric distribution early joint-space narrowing osteopenia.
JOINT INFECTION rapid destruction of joint space loss of the lamina dura (articular cortex) over a continuous segment of the bone. AMYLOIDOSIS Bilateral and symmetric Periarticular osteopenia is frequent.
XANTHOMATOSIS foci of soft-tissue deposition of cholesterol and lipid products. Laboratory work-up for differentiation OSTEOARTHRITIS elderly women symmetric distribution Erosion of the joint space
X-RAY FILM COMPUTED TOMOGRAPHY (CT) SCANS MAGNETIC RESONANCE IMAGING (MRI) ULTRA SOUND
normal mineralization joint space preservation sharply marginated erosions with sclerotic borders overhanging edges asymmetric polyarticular distribution LIMITATIONS Indicates the chronicity 6-8 years after the initial attack
reveal MSU deposits in vitro as well as within the knee joint readily diagnose stones of the urinary tract not visible on conventional radiographs
detects early subclinical tophaceous deposits determining the extent of disease in tophaceous gout provides information regarding the patterns of deposition and spread of MSU crystals.
more reliable, noninvasive method for diagnosis can detect deposition of MSU crystals on cartilaginous surfaces, as well as tophaceous material and typical erosions
ASYMPTOMATIC HYPERURICEMIA Usually requires No treatment except in: Elevated Serum Uric acid level Positive Family history of tophaceous gout Treated with Allopurinol under closed medical observation
ACUTE GOUTY ARTHRITIS Joint immobilization Colchicines Nonsteroidal anti-inflammatory agents(nsaids) Corticosteroids Uricosuric agents and allopurinol are of no value in treatment of the acute attack.
INTER-CRITICAL GOUT (INTERVAL PERIOD) PREVENTIVE MEASURES
CHRONIC GOUTY ARTHRITIS Allopurinol is the drug of choice Uricosuric drugs, such as Probenecid and Sulfinpyrazone, may also be used In selected patients, large deforming tophi may be excised surgically
DR. GILLIAN LIEBERMAN GRAHAM FRANKEL DR. VERONICA FERNANDES DIKSHITA DUBEY SNEHANSH ROY CHAUDHARY TEJESHWAR SINGH JUGPAL
Brant WE, Helms CA. Fundamentals of Diagnostic Radiology. 2nd ed. 1999 Lippincott Williams & Wilkins Philadelphia Ruddy et al. Kelley's Textbook of Rheumatology. 6th ed. 2001 W. B. Saunders Company Weissleder R, Wittenberg J, Harisinghani MG. The Primer of Diagnostic Imaging. 3rd ed. 2003 Mosby, Inc. Philadelphia "Diagnostic Radiology/Musculoskeletal Imaging/Joint Disorders/Gout - Wikibooks, Collection of Open-content Textbooks." Wikibooks. Web. 19 Aug. 2010. <http://en.wikibooks.org/wiki/diagnostic_radiology/musculoskeletal_imaging/jo int_disorders/gout>. Ferguson, Mark. Gout. Print. "Gout." Dr. Amilcare Gentili's Radiology Education Publications on the Internet" Web. 18 Aug. 2010. <http://www.gentili.net/hand/gout.htm>. Schlesinger, Naomi. "Diagnosis of Gout: Clinical, Laboratory, and Radiologic Findings." AJMC - American Journal of Managed Care. Web. 20 Aug. 2010. <http://www.ajmc.com/media/pdf/a141_diagnosis>. Smelser, Christopher D. "Gout." EMedicine - Medical Reference. Web. 19 Aug. 2010. <http://emedicine.medscape.com/>. Web. 20 Aug. 2010. <http://www.gout.com/causes-triggers.aspx>. Zayas, Vanessa M. "Gout: The Radiology and the Clinical Manifestations." Applied Radiology Online - The Journal of Practical Medical Imaging and Management. Web. 16 Aug. 2010. <http://www.appliedradiology.com>