SCLERODERMA

Scleroderma is an autoimmune disorder of predominantly adults, characterized by hardening of—(a) skin due to chronic fibrosis of dermis and deeper tissues, and/or (b) arteries of internal organs specially lungs, kidney and GIT with systemic manifestations.

Etiopathogenesis is autoimmune, suggested by—

(a) histological features, i.e. destruction of vascular endothelium, cellular infiltration, fibroblast proliferation and increased collagen synthesis, and (b) presence of antinuclear antibodies in some cases. Rarely, drugs, e.g. bleomycin or chemicals, e.g. PVC exposure has been implicated as triggering event.

Clinically, Raynoud phenomena, i.e. transient episodes of pallor followed by cyanosis and then followed by erythema (3-stages), over fingers and toes after cold exposure due to arterial spasm in digits, is the earliest manifestation preceding skin and visceral manifestations.

Localized scleroderma is more common in children, presenting with discrete lesions (morphea) on trunk or linear lesions on extremities, which begin as an inflammatory patch but rapidly evolve to indurated, depigmented and atrophic lesions with tightening of skin. Fibrosis sometimes extends to deeper tissues, e.g. muscles and bones, leading to contractures, limb­shortening and cosmetic deformities.

Systemic sclerosis is extremely rare in childhood, presenting with (a) progressive dermal involvement, with flexion contractures, and (b) multi-systemic involvement, e.g. progressive pulmonary interstitial fibrosis, hypertension, dysphagia and CCF or arrhythmias due to cardiac fibrosis.

TABLE 24.9: Diagnostic criteria for Juvenile systemic sclerosis

• Major criteria (required)

- Proximal skin sclerosis or induration

• Minor criteria (at least 2)

- Sclerodactyly

- Peripehral vasculopathy*

- Dysphagia, gastroesophageal reflux

- Cardiac arrhythmia, CCF

- Renal crisis, hypertension

- Pulmonary AbrosisZhypertension

- Neuropathy, carpal-tunnel syndrome

- Tendon friction rubs, arthritis, myositis

- Serology: Positive for antinuclear antibodies**

• Raynaud phenomenon, nail-fold telangiectasias, digital tip ulcers

** SSc-selective autoantibodies (anticentromere, antitopoisomerase I [Scl-70], antifibrillarin, anti-PM/Scl, antifibrillin or anti-RNA polymerase I or III)

Abridged from ES/ACR/EULAR criteria 2007

Diagnosis is clinical, supported by nail-fold capillaro- scopy to reveal vascular changes (loss, tortuosity, bushy capillaries) and presence of antinuclear antibodies (Table 24.9).

Serial pulmonary function tests for vital capacity and CO-diffusion capacity are indicated to assess lung functions..

Treatment depends on the severity of disease and includes:

• Immunosuppressive therapy with steroids (PO Pre­dnisolone 2 mg/kg/day) or SC Methotrexate (15 mg/ m²#8725;week) or both, for 4-6 months. Mycophenolate is the second-line drug for recalcitrant disease.

• Physical and occupation therapy for contractures.

• Avoidance of cold-exposure (gloves) and drugs, e.g. nifedipine or topical vasodilators to prevent Raynaud phenomenon.

Prognosis is variable, with regression or stabilization of localized lesions after many years, or progression to systemic sclerosis with death due to end-stage pulmo­nary, renal or cardiac disease.

Other rare but important connective tissue disorders in children include:

Sjogren syndrome is a chronic inflammatory disease of autoimmune origin, clinically characterized by: (a) dry eyes, e.g. keratoconjunctivitis sicca or xerophthalmia,

(b) dry mouth, i.e. xerostomia, and (c) systemic mani­festations of connective tissue disease involving skin, muscles and joints, serosal cavities and CNS or other organs. It is typically seen in females (9:1) of 35-45 years age, rare in children.

Beh#962;et's disease is a rare multi-systemic disorder in childhood, characterized by recurrent oral and genital ulcerations with/without other manifestations of connective tissue involvement.

Mixed connective tissue disease (MCTD) is a multi- systemic disorder, characterized by overlapping features of JRA, SLE, systemic scleroderma and dermatomyositis. These patients characteristically have high titers of U1- anti-ribonucleoprotein (anti-RNP) antibodies, along with anti-DNA antibodies. Treatment includes low-dose steroids/NSAIDs and long-term weekly methotrexate therapy.