Updates on Pediatric Rheumatologic Diseases
Anju Gupta1, * 1 Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Abstract
Rheumatological disorders pose a challenge to clinicians because of multisystemic involvement, relapsing-remitting course, and nonspecific clinical features, which can mimic infections, malignancies, and even genetic disorders. Common symptoms at presentation are joint pain, fever, weight loss, malaise, muscle weakness, rash, and ulcers. While diseases, such as juvenile idiopathic arthritis, juvenile dermatomyositis, and IgA vasculitis, are relatively easy to diagnose because of typical clinical manifestations, others such as systemic lupus erythematosus, scleroderma, and various vasculitides are much more challenging. No laboratory investigation is diagnostic of a particular rheumatological disorder. Investigations, such as antinuclear antibodies and antineutrophilic cytoplasmic antibodies, are associated with a high false-positive rate and should be used judiciously. Most diseases except for Kawasaki disease and IgA vasculitis are chronic and require long-term immunosuppression for control of disease activity. Long-term prognosis has improved over the past few decades due to better immunosuppressive regimens and better monitoring. With an improvement in mortality rates, many children are living into adulthood and facing issues with persistent disease activity and morbidity related to therapeutic regimens. Future research should focus on finding better therapeutic protocols, which should result in further improvements in survival while simultaneously reducing drug toxicity. There is also an urgent need to define better monitoring tools for most rheumatological conditions.
Keywords: ANCA associated vasculitis, Antiphospholipid syndrome, IgA vasculitis, Juvenile dermatomyositis, Juvenile idiopathic arthritis, Juvenile systemic sclerosis, Kawasaki disease, Localized scleroderma, Macrophage activation syndrome, Neonatal lupus, Polyarteritis nodosa, Rheumatological disorders, Systemic lupus erythematosus, Takayasu arteritis, Uveitis, Vasculitis.
* Corresponding author Anju Gupta: Department of Pediatrics, Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India; Tel: +91-7087008315; Fax: 91-172-2745078;
E-mail: [email protected] RHEUMATOLOGICAL DISEASES IN CHILDREN
Rheumatological diseases pose a real challenge to physicians because of multiple reasons. Signs and symptoms may either be non-specific like fever, weight loss,
malaise, rash, and joint pains or may point to any organ system in the body. For this reason, these patients may present to any subspecialty of pediatrics. The differential diagnosis in such settings is wide, ranging from infections, inflammatory conditions, malignancies, and sometimes even genetic disorders.
Common manifestations with which patients are brought to pediatric rheumatological services are joint pain, fever, weight loss, malaise, muscle weakness, rash, and ulcers. This chapter will discuss the differential diagnosis of common rheumatological symptoms before discussing specific rheumatological conditions and their management.
When to Suspect Rheumatologic Disorders
Approach to a Child with Joint Pains
Joint pain is the most common symptom of children presenting to pediatric rheumatology services. Physicians need to be able to answer the following three questions after history and physical examination in children presenting with body pains:
- Whether the pain is articular or not?
- If articular,
- Is the pain inflammatory or non-inflammatory?
- In case of inflammatory articular pain
- Is the involvement acute or chronic?
- The pattern of joint involvement: Number of joints involved, symmetry of involvement, peripheral vs. axial involvement, small vs. large joint involvement, fixed vs. migratory vs. additive involvement.
- Presence or absence of extra-articular features.
These three questions help in the further differential diagnosis. Pediatric gait, arms, legs, and spine (pGALS) test is a useful screening tool for musculoskeletal examination [1]. Though it is not specific to joint disease, it has been shown to improve musculoskeletal examination skills. Detection of any abnormality in pGALS should be followed by a detailed and focused examination of joints and supporting structures.
Whether the Pain is Articular or Not?
Articular pain tends to occur across joint lines, whereas the location of non-articular pain may vary. Articular pain is usually deep, diffuse, occurs along all planes of movement, and occurs on both passive and active movements (Table 1). Such pain suggests pathology in the synovium, cartilage, and joint capsule.
Table 1 Differences between articular and periarticular pain. Clinical Feature | Articular Pain | Periarticular Pain |
Anatomic structure | Synovium, cartilage, capsule | Tendon, bursa, ligament, muscle, bone |
Location of pain | Diffuse, deep | Focal “pin-point” |
Pain on movement | Active/passive, in all planes | Active, in a few planes |
Swelling | Common | Uncommon; focal if present |
On the other hand, periarticular pain is more focal, rather pinpoint, and occurs in few planes. Periarticular pain gets exacerbated with active movements. Such pain is seen due to pathology in tendons, bursa, ligaments, muscles, or bone. Common etiologies are enthesitis, fractures, and osteomyelitis in the metaphyseal region.
Is the Pain Inflammatory or Non-inflammatory?
Inflammatory pain is associated with early morning stiffness and gelling. Early morning stiffness refers to pain and difficulty in moving the joints in the morning on waking up, and it usually tends to last for half an hour or more. Gelling is similar to early morning stiffness but tends to happen after prolonged rest in the daytime. Joint swelling (Fig. 1) is also indicative of joint inflammation. Redness over the joint is rarely seen except in septic arthritis and reactive arthritis. Warmth and limitation of movement of joints also point to inflammatory causes (Table 2).
Fig. (1)) Joint swelling in both knees suggestive of arthritis.
Table 2 Differences between inflammatory and noninflammatory articular pain. Clinical Feature | Inflammatory Articular Pain | Noninflammatory Articular Pain |
Pain | Morning | Evening |
Swelling | Soft tissue | Bony |
Redness | Occasional | Absent |
Warmth | Sometimes | Absent |
Stiffness | Prominent | Usually absent |
Limitation of joint movements | Frequent | Absent |
Systemic features | Sometimes | Absent |
Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) | Usually elevated | Not elevated |
Pains occurring predominantly at night are more typical of malignancies like acute leukemia or neuroblastoma. In such a setting, pain is not restricted to the joint line. Other red flag signs for malignancy are inability to bear weight, severe pain needing intravenous analgesics, and symptoms disproportionately more than signs.
Noninflammatory articular pain is typical in hereditary arthropathies, intraarticular arteriovenous malformations, hypermobility, and certain orthopedic conditions such as Perthes disease or avascular necrosis of the femoral head and slipped upper femoral epiphysis. Children with hereditary coagulopathy may show features of inflammation like warmth, swelling, and limitation of movements in a joint with acute hemarthrosis.
Is the Involvement Acute or Chronic?
The duration of articular involvement helps to narrow down the diagnosis. Wh...