Faculty Development Case of the Month: September 2022

Monthly Case from the Division of Rheumatology
“The Case of the Great Imitator”

Submitted by:
Aesha Singh, MBBS
Fellow
Division of Rheumatology
Department of Medicine

Edited by:
Arezou Khosroshahi, MD
Associate Professor of Medicine
Division of Rheumatology
Department of Medicine

A 24-year-old woman was admitted for evaluation of progressive diffuse joint pain for five days. Two weeks preceding the joint pain, she developed three days of diarrhea, nausea, and vomiting. Following resolution of her initial symptoms, she continued to have progressive malaise, decreased appetite, generalized weakness, diffuse joint pain and redness with inability to ambulate. On examination, she had icterus with erythema on her face. She had polyarticular inflammation with synovitis bilaterally at her shoulders, elbows, metacarpophalangeal, proximal interphalangeal, knees, ankles, midfoot and Achilles tendon area. Pertinent negatives included the absence of fever, lymphadenopathy, and hepatosplenomegaly. Initial labs showed acute kidney injury (AKI), elevated liver enzymes, electrolyte imbalances, leukocytosis, and elevated inflammatory markers (see table below).

She did not have any pertinent past medical history and denied any active alcohol or substance abuse. She was not aware of any family history of autoimmune diseases.

Her presentation was concerning for systemic inflammation with multiorgan failure. It was thought that a decrease in oral intake and dehydration contributed to the AKI, but her liver enzymes elevation, leukocytosis and polyarthritis were suggesting an infectious or an autoimmune process. We recommended to start her on IV methylprednisolone 20 mg every 12 hours while the workup was done.

 

LABORATORY STUDIES:

Sodium –136 mmol/L	White blood cells – 47800
Potassium – 2.7 mmol/L	Neutrophils – 44930
Blood Urea nitrogen- 117 mg/dL	Hemoglobin- 10.6 gm/dL
Creatinine- 3.12 mg/dL	Erythrocyte sedimentation rate (ESR) >130 mm/hr
Bilirubin- 3.6 mg/dL	C reactive protein (CRP) 196 mg/L
Bilirubin Total-2.23 mg/dL	Viral Hepatitis – Negative
Aspartate transaminase– 80 Unit/L	HIV Antigen/Antibody- negative
Alanine transaminase– 73 Unit/L	Urine culture – no growth
Alkaline Phosphatase – 370 Unit/L	Blood culture – no growth
Aldolase – 14.5 Unit/L	Chlamydia/Gonococcal/Trichomonas RNA – Negative
Creatinine phosphokinase- <10 Unit/L	Rapid plasma reagin- Negative
	Anti-streptolysin O – negative

Autoimmune serologies:

• ANA (antinuclear antibody) by Immunofluorescence, ANA screen with reflux, double stranded DNA (dsDNA), Rheumatoid factor (RF), cyclic citrullinated peptide (CCP), Myositis panel, Lupus anticoagulant panel, Antiphospholipid antibody panel: negative
• HLAB27: negative
• Complement 3: 69 mg/dL (Normal 81-157); Complement 4: 1 mg/dL (Normal 13-39)

Ultrasound Abdomen:
Gall bladder sludge without cholecystitis

Hospital Course:

Her arthritis improved within a day of IV steroids with gradual improvement in her AKI, liver enzymes and leukocytosis. She was discharged on oral prednisone which was tapered over a month and on follow up her arthritis had completely resolved. Her ESR and CRP also normalized.

FINAL DIAGNOSIS

Reactive arthritis and significant dehydration and malnutrition due to arthritis

DISCUSSION

Reactive arthritis (ReA) is a sterile inflammatory synovitis occurring within 4 weeks of infection elsewhere in the body, primarily urogenital or enteropathic. It is more commonly seen in ages 20-40 and more in men. Pathogenesis of ReA involves a complex interaction of genes (HLA B27), microbes and environment. Patients usually present with articular (arthritis, enthesitis, dactylitis, sacroiliitis) and extraarticular manifestations. The diagnosis is clinical, but laboratory investigations which can support the diagnosis include ESR, CRP, leukocytosis, urinalysis, cultures, and/or PCR (throat, urine, stool, blood, urethra, synovial fluid, cervix) for Chlamydia, Yersinia, and Salmonella, RF, ANA.

Treatment of ReA usually includes NSAIDS, antibiotics, intraarticular steroids. However, if there is a poor response, one could consider systemic steroids. Over 50% of patients have a self-limited course lasting 3 to 5 months, 30% have recurrent episodes, and 15% to 20% have a chronic course requiring immunosuppressive therapy.

Reference:

Rheumatology secrets, chapter 36.