PERSISTENT KNEE SWELLING IN A LUPUS PATIENT Pediatric Rheumatology Case Dr. Christine Bernal IIIB-4 PERSISTENT KNEE SWELLING IN A LUPUS PATIENT

Salient Features

Salient Features Luisa, 16 y/o, female Diagnosed with SLE at 12 Prolonged fever Malar rash Photosensitivity Hair loss Oral ulcers Easy fatigability Anemia Neutropenia Thrombocytopenia (+) ANA (+) anti-dsDNA

In January 2009…. Pain on the L knee with swelling after a fall With fever and chills Self-medicated with Ibuprofen for 2 weeks, no improvement

PE Findings Ill-looking Wheelchair borne BP: 110/70 CR: 102/min RR: 24/min Temp: 39.8°C No rash or oral lesions Regular heart rate and rhythm No murmur or rub Regular heart rate and rhythm No murmur or rub Clear breath sounds Soft non-tender abdomen, no hepatosplenomegaly L knee – warm tender and swollen w/ limited ROM

ACR Criteria for SLE

ACR Criteria for SLE presence of four or more of the following 11 criteria, serially or simultaneously, during any period of observation Malar rash Discoid rash Photosensitivity Oral ulcers Arthritis (non-erosive) Serositis (Pleuritis or Pericarditis) Renal disorder persistent proteinuria > 500 mg per 24 hours (0.5 g per day) or > 3+ cellular casts Neurologic disorder Hematologic disorder hemolytic anemia with reticulocytosis leukopenia, < 4,000 per mm3 (4.0 _ 109 per L) on two or more occasions lymphopenia, < 1,500 per mm3 (1.5 _ 109 per L) on two or more occasions thrombocytopenia, < 100 _ 103 per mm3 (100 _ 109 per L) in the absence of offending drugs Immunologic disorder Antinuclear antibodies

In the patient… Malar rash Photosensitivity Oral ulcers Anemia Thrombocytopenia (+) ANA (+) anti-dsDNA L knee – warm tender and swollen w/ limited ROM

Initial Impression and Differential Diagnosis

What is your Initial Impression? Patient: Immunocompromised ill looking Fever and chills SEPTIC ARTHRITIS probably bacterial infection Left Knee: + trauma Abrupt in onset < 2weeks (acute) Unilateral pain and swelling, warm Limited range of motion

SEPTIC ARTHRITIS Occurs as a result of hematogenous seeding of infectious organism in the synovial fluid Consequence of inflammatory reaction joint cartilage and synovial are damage by the proteolytic enzymes and mechanical factors. Common in young children

SEPTIC ARTHRITIS Etiologic Agent: Staphylococcus aureus (most common) Gonococcal (sexually active) Candida (disseminated infection) Viral (systemic infection)

SEPTIC ARTHRITIS Infection of joints are followed by Penetrating injuries: Trauma Arthroscopy Prosthetic Joint Surgery Intra-articular Steroid Injection Orthopedic Surgery

Differential Diagnosis Juvenile Rheumatoid Arthritis Onset < 16 y/o Persistent arthritis in at least one joint for 6 weeks polyarticular course and functional disability symmetric, large and small joints Exclusion for other diagnoses Girls > boys production of JRA – causes synovial inflammation, bone erosion, fever, rash, joint destruction; can be treated with biologic agents

Differential Diagnosis Systemic Lupus Erythematosus An episodic, multisystem, autoimmune disease Widespread inflammation of blood vessels and connective tissues Intermittent Polyarthritis Mild from disabling Characterized by soft tissue swelling and tenderness in joints of the hands, wrist, and knees Presence of autoantibodies (hallmark of SLE)

Differential Diagnosis Drug induced: Glucocorticoid treatment Can cause osteopenia and osteonecrosis Hydrochloroquine Can cause osteonecrosis

WORK - ups

Erythrocyte sedimentation rate (ESR) and C reactive protein Culture of the synovial fluid or of synovial tissue itself is the only definitive method of diagnosing septic arthritis. Erythrocyte sedimentation rate (ESR) and C reactive protein useful to screen for infectious and rheumatic diseases A normal ESR value does not exclude rheumatic disease. Infections = increased ESR High values persisting for more than several weeks may necessitate further evaluation, depending on the associated symptoms, physical findings, and other laboratory abnormalities.

RF (Rheumatoid-factor) ANA test a screening test for specific anibodies against nuclear constituents A positive titer (≥1 : 80) is a nonspecific reflection of increased lymphocyte activity RF (Rheumatoid-factor) seropositivity may be associated with onset of polyarticular involvement in an older child (≈8%) and the development of rheumatoid nodules

Anti–double-stranded DNA are more specific for lupus often reflect the degree of serologic disease activity Serum levels of total hemolytic complement (CH50), C3, and C4 decreased in active disease and provide a second measure of disease activity Anti-Smith antibody found specifically in patients with lupus, does not measure disease activity

MANAGEMENT

The goals of management would include: To treat the fever To protect the organs by decreasing inflammation and/or the level of autoimmune activity in the body -- To reduce the swelling and relieve the pain on her left knee

To reduce the swelling and relieve the pain on her left knee Medical management of infective arthritis focuses on the: Adequate and timely drainage of the infected synovial fluid. Administration of appropriate antimicrobial therapy. Immobilization of the joint to control pain.

The empirical choice of antibiotic therapy is based on results of the Gram stain and the clinical picture and background of the patient. Initial antibiotic choices must be empirical, based on the sensitivity pattern of the pathogens. Because many isolates of group B streptococci have become tolerant of penicillin, use a combination of penicillin and gentamicin or a 2nd or 3rd -generation cephalosporin.

Preferably, the antibiotic should be bactericidal with some effect against the slow-growing organisms that are protected within a biofilm. Rifampin fulfills these requirements. It should never be used alone because of the rapid development of bacterial resistance to the drug.

Surgical Care Surgical drainage is indicated when one or more of the following occur: The appropriate choice of antibiotic and vigorous percutaneous drainage fails to clear the infection after 5-7 days. The infected joints are difficult to aspirate (eg. hip), or adjacent soft tissue is infected.