Rheumatology Flashcards
A 15-year-old girl presents with:
Severe fatigue
Weight loss
Fever
Pain in cervical spine, bilateral hip, bilateral shoulder, and right jaw, with evidence of arthritis in these joints on examination
Laboratory:
Rheumatoid factor (RF) positive
Anticyclic citrullinated peptide antibodies (anti-CCP) present
Antinuclear antibody negative
What is the diagnosis?
Polyarticular juvenile idiopathic arthritis (poJIA), RF-positive (poJIA RF+)
Explanation
poJIA involves ≥ 5 joints during the first 6 months and is found in 30–40% of those diagnosed with JIA. It is much more common in girls (3:1 over boys). There are 2 distinct groups: those who are RF positive and those who are RF negative. The RF-positive group is diagnosed in only ∼ 4–5% of children with JIA; this disease most commonly strikes adolescents. Having RF-positive JIA is like having adult rheumatoid arthritis—these children must be managed aggressively with disease-modifying antirheumatic drugs. Fatigue is one of the most common presenting symptoms. Anti-CCP antibodies signify that erosive arthritis is likely. Uveitis may occur but not as commonly as in oligoarticular JIA.
A 4-year-old girl of Turkish ancestry presents with:
Fever of 3 days duration that occurs every month, accompanied by severe abdominal pain
An erysipelas-like rash around the ankles
Laboratory during episodes: ESR 70 mm/hour, elevated C-reactive protein (CRP), WBC 25,000/µL
Laboratory not during episodes: ESR 12 mm/hour; normal CRP; WBC 7,000/μL
What is the likely diagnosis?
Answer
Familial Mediterranean fever (FMF; a.k.a. familial paroxysmal polyserositis, familial recurrent polyserositis)
Explanation
FMF is an autosomal recessive disorder mainly seen in Armenians, Turks, Levantine Arabs, and those of Sephardic Jewish descent. Most children have attacks of fever that can last from several hours to 5 days. The fever typically recurs in predictable cycles (e.g., 3–5 days every month in one patient, several times a year in another). Classically, the labs listed are abnormally elevated during disease episodes and return to normal during the interval periods.
A 4-year-old boy presents in winter after an upper respiratory infection with:
A rash on the buttocks and lower extremities that began as small wheals and red maculopapules that have become petechial and purpuric
Periarthritis of the knees and ankles
Colicky abdominal pain
Laboratory:
WBC 25,000/µL
ESR 58 mm/hour
Platelets normal
Prothrombin time/activated partial thromboplastin time normal
Urine with 3–5 RBCs/high power field
What is the most likely diagnosis?
Immunoglobulin A vasculitis (IgAV)
Explanation
IgAV commonly presents with periarthritis, colicky abdominal pain, and microscopic hematuria. The WBC and ESR are elevated, whereas platelets and coagulation studies are normal. IgA immune complexes are often seen in the tissue biopsy specimens of affected vasculitic tissues.
A 15-year-old presents with arthritis. You are concerned about juvenile idiopathic arthritis (JIA) vs. systemic lupus erythematosus (SLE). Radiographs of the affected joints are taken.
What do you expect to see in JIA compared to SLE as far as x-ray effect?
JIA can cause erosive joint damage; SLE does not.
Explanation
Realize that JIA can cause juxtaarticular osteopenia and erosive joint damage, but this occurs relatively late in the course. In contrast, SLE usually does not cause any erosive damage to the joint. Be aware, though, that SLE commonly causes avascular necrosis, especially of the hips, knees, and shoulders. SLE can cause a nonerosive joint abnormality called Jaccoud arthropathy, a reversible subluxation at the metacarpophalangeal joints of the hands.
A 2-year-old girl presents with:
Severe fatigue
Weight loss
Fever
Pain in cervical spine, both hips, both shoulders, and right jaw, with evidence of arthritis in these joints
Laboratory:
Negative rheumatoid factor (RF)
Positive antinuclear antibody (ANA)
What is the diagnosis? What is the significance of the ANA in this disease process?
Polyarticular juvenile idiopathic arthritis, RF-negative (poJIA RF−); increased risk of uveitis with positive ANA
Explanation
poJIA involves ≥ 5 joints at time of presentation/diagnosis and is found in 30–40% of those diagnosed with JIA. It is much more common in girls than in boys (3:1). There are 2 distinct groups: those who are RF positive and those who are RF negative. The RF-positive group is usually adolescents; the RF-negative group has 2 peaks: toddler age and 9–14 years of age. About 50–80% of children with RF-negative poJIA have a positive ANA. Younger children (< 7 years of age) with poJIA and positive ANA have an intermediate risk of uveitis; they must be monitored for it, but their risk is less than that of children with oligoarticular JIA and positive ANA.
A 15-year-old girl presents with:
Multiple areas of pain (sometimes sharp and sometimes dull) that have occurred almost daily for the past year
A history of anxiety managed with cognitive-behavioral therapy
Sleep that is not restful
Fatigue
On physical examination, you find the following tender areas on digital palpation:
Bilateral trapezius muscle midpoint
Bilateral supraspinatus at the origin of the scapula near the medial border
Bilateral lateral epicondyle 2 cm distal to the epicondyle
Bilateral gluteal area in the upper outer quadrants
Bilateral medial fat pad of the knee
What is the most likely diagnosis?
Juvenile (primary) fibromyalgia
Explanation
This is the classic presentation for fibromyalgia: an adolescent female with any combination of widespread musculoskeletal aches and pain and any combination of poor sleep, fatigue, headache, cognitive complaints, and anxiety. Tender myofascial points may or may not be present.
A 12-year-old girl with a history of Salmonella diarrhea 2 weeks ago presents with:
Subjective fever
Conjunctivitis
Oral ulcers
WBCs in her microscopic urine test
Arthritis of her left knee and right ankle
What is the diagnosis?
Reactive arthritis
Explanation
Reactive arthritis (formerly postinfectious arthritis, Reiter syndrome) occurs 1–4 weeks after a gastrointestinal (GI) infection with Yersinia, Shigella, Salmonella, or Campylobacter or after a genitourinary infection caused by Chlamydia. Other organisms, such as Clostridioides (formerly Clostridium) difficile and Giardia, can also trigger the illness. The classic triad (not typically seen in younger children) of urethritis, conjunctivitis, and arthritis has the mnemonic, “can’t pee, can’t see, can’t climb a tree.” Urethritis occurs even if the infectious trigger was GI in origin; urinalysis may show a sterile pyuria.
An 18-year-old male presents with:
Fever
Weight loss
Migratory arthralgias of his hips and knees
Cough and nasal stuffiness
Occasional epistaxis
“Saddle nose”
Nodules throughout his lungs on chest x-ray
Elevated creatinine of 2.0 mg/dL
Positive cytoplasmic antineutrophilic cytoplasmic antibody (c-ANCA)
What is the most likely diagnosis?
Answer
Granulomatosis with polyangiitis (formerly Wegener’s)
Explanation
This young man has classic signs and symptoms of a “pulmonary-renal” syndrome. It can present in adolescence, but mostly occurs in adults, males and females equally. The “saddle nose” is a nasal deformity seen in this disorder. In children, you can also see subglottic stenosis. Renal involvement is uncommon in children at presentation but eventually occurs in 60–70% of cases. c-ANCA is found in > 90% of those with diffuse disease and is a big clue if found in an exam question.
A 3-year-old boy presents with:
Fever of 5–7 days’ duration occurring every 4 weeks
Aphthous ulcers of the mouth
Sore throat
Cervical lymphadenitis
No current or history of neutropenia
What is the diagnosis?
Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome
Explanation
PFAPA is a benign syndrome that typically begins in children 5 years old or younger (the mean age is ~ 3 years). It is a relatively common disorder with no known genetic cause. The diagnosis is based on the fever pattern and physical exam. In contrast to familial Mediterranean fever, the fever generally lasts longer in PFAPA (on average 5 days). Some children have joint pain, abdominal pain, rash, headache, vomiting, or diarrhea. The flares respond quickly to prednisone. The average periodicity of febrile episodes is 4 weeks and is not accompanied by any sign of infection.
A 14-year-old girl presents with:
Recurrent parotitis
Dry eyes
Conjunctival inflammation
Dryness of the mouth
Laboratory positives:
Rheumatoid factor (RF)
Antinuclear antibody (ANA)
Anti-Ro
What is the most likely diagnosis?
Sjögren syndrome (SS)
Explanation
Always suspect SS in a child with recurrent parotitis. Most cases will present with recurrent parotitis and keratoconjunctivitis sicca (the dry eyes plus conjunctival inflammation). The laboratory may show any of the listed antibodies, so do not be fooled by the positive ANA into diagnosing systemic lupus erythematosus (SLE). Remember: She does not have enough criteria for SLE. Also, she has nothing here to make you think of juvenile idiopathic arthritis, so the positive RF is not an indication of that.
A 32-year-old woman with systemic lupus erythematosus (SLE) presents with a history of multiple miscarriages.
What class of antibodies is most likely responsible for her multiple miscarriages?
Antiphospholipid antibodies
Explanation
Women with SLE and a history of recurrent miscarriages are likely to have antiphospholipid antibodies. These include lupus anticoagulant, anticardiolipin, and β2-glycoprotein-1 antibodies. Additionally, these antibodies can cause thrombocytopenia, livedo reticularis, and/or blood clots in about 25% of patients.
A 9-year-old girl is found to have the following on physical exam:
Knees hyperextend 14° bilaterally.
Elbows hyperextend 12° bilaterally.
Patient is able to rest both palms on the floor with her knees fully extended.
Wrist hyperextends so fingers are parallel to dorsum of forearm.
Patient can passively touch thumb to flexor aspect of the forearm.
Whatdo these physical findings indicate? Based on these findings, what else do you look for?
Hypermobility syndrome; other signs of inherited diseases of connective tissue
Explanation
This patient has every finding of benign hypermobility joint syndrome, which occurs in about 4–13% of normal children. The ability to perform these tasks in ≥ 5 locations (a point for each side of the body plus flexing the trunk) indicates hypermobility on the Beighton scale. If found, look at the family history and for other signs of inherited diseases of connective tissue, especially Ehlers-Danlos syndrome and Marfan syndrome. For most children, hypermobility joint syndrome is a benign condition with no other findings, although joint and muscular pain, as well as transient joint effusions, can occur.
A 7-year-old child presents with:
Fever to 103.0°F (39.4°C) in the evening on a daily basis
Rash—described as macular, pink to salmon colored with discrete borders—that comes on with the fever
Synovitis and arthritis of the left knee and the right wrist
Severe myalgias
No uveitis
Hepatosplenomegaly
Laboratory: WBC 30,000/µL, platelets 850,000/µL, ESR 56 mm/hour, anemia of chronic disease, rheumatoid factor negative, antinuclear antibody (ANA) negative
What is the diagnosis?
Answer
Systemic juvenile idiopathic arthritis (sJIA)
Explanation
The laboratory findings listed are classic for sJIA. The peak age at onset is between 1 and 5 years of age, with boys and girls equally affected. (Our 7-year-old is not typical, but the scenario is entirely plausible as older children and adolescents may also be diagnosed with sJIA.) The salmon-colored rash is classic and typically appears with the daily fevers that more commonly occur in the evening. These children may also have twice daily fever and myalgia. Synovitis must be present to make the diagnosis, although it may not appear initially. Arthritis can be in a few (oligoarticular) or, more typically, in multiple joints (polyarticular), so do not let the low number of joints here fool you. Uveitis is not common, unlike in oligoarticular JIA. Hepatosplenomegaly, weight loss, and fatigue are common. The negative ANA helps distinguish this from systemic lupus erythematosus. In a patient such as this, one must also consider bone and joint infection or hematologic malignancy.
A 17-year-old boy with a history of Crohn disease presents with sacroiliac pain and arthritis. He is not having a gut flare and is known to be human leukocyte antigen (HLA)-B27 positive.
What is the diagnosis of his arthritis?
Arthritis associated with inflammatory bowel disease (IBD)
Explanation
Arthritis occurs in ∼ 25% of patients with IBD (Crohn’s or ulcerative colitis). The arthritis has the following characteristics:
If peripheral joints are affected (more commonly):
Equally common in boys and girls
Not associated with HLA-B27
Presents with gut flares
If axial in nature:
More common in boys
Associated with HLA-B27
Not associated with gut flares
A newborn presents with:
Congenital complete heart block
Raised, erythematous annular rash on the scalp and face
Which 2 antibodies did the mother likely have that affected this newborn?
Anti-SSA (anti-Ro) and anti-SSB (anti-La) antibodies
Explanation
This newborn has neonatal lupus erythematosus as a result of transplacentally acquired maternal antibodies, specifically anti-SSA (anti-Ro) and anti-SSB (anti-La). In mothers with these antibodies, the risk of the newborn developing neonatal lupus erythematosus is 2%; a small risk but significant enough that the mother and fetus should be followed throughout pregnancy. Postpartum, monitor the infant for 12 months for any ongoing cardiac conduction abnormalities, including a prolonged QTc syndrome interval.
