Genodermatoses
A number of genodermatoses also contribute to persistent wounds in the pediatric population; specifically, genodermatoses that predispose to neuropathies and decreased pain sensation, which affect the child’s ability to detect sensation in the lower extremities, can result in inadvertent trauma leading to refractory wounds. For example, hereditary, sensory, and autonomic neuropathies are rare disorders causing progressive distal sensory loss, leading to ulcerations, osteomyelitis, arthritis, and even amputation.16 Hereditary, sensory, and autonomic neuropathies are further categorized into several different types; however, the unifying theme of diminished sensation is the culprit for troublesome wounds. Therapeutic endeavors to maximize preventative care with orthotics are vital in allaying recurrent wounds in these patients. Another uncommon hereditary disorder that promotes poor wound healing is caused by an inborn error of collagen synthesis. Prolidase deficiency is an autosomal-recessive condition resulting in characteristic facies, recurrent infections, and recalcitrant leg ulcerations due to impaired collagen formation.17 More than 50% of affected patients experience leg ulcers comprised of irregular borders with prominent granulation tissue. Treatment is aimed at restoring collagen synthesis and optimizing wound healing with the use of topical proline, glycine, and even growth hormone to promote repair.18 Additional genodermatoses predisposing to leg ulcerations include Lesch-Nyhan syndrome due to self-mutilating behaviors and epidermolysis bullosa due to impaired barrier and a decreased ability to repair cutaneous defects.
Autoimmune Causes
Although a much smaller category, ulcers due to autoimmune etiologies were reported in the literature. Fibrosing disorders including morphea and scleroderma can cause extensive disease in severe cases. Disabling pansclerotic morphea of childhood can cause sclerosis that extends into muscle, fascia, and even bone, resulting in contractures and ulcerations.4 The initial areas of involvement are the arms and legs, followed by spread to the trunk and head and neck area.4 Immunosuppressant therapy is needed to halt disease progression. Pediatric cases of systemic lupus erythematosus also have been associated with digital ulcers. One case was thought to be due to vasculitis,19 and another resulted from peripheral gangrene in association with Raynaud phenomenon.20 Albeit rare, it is important to consider autoimmune connective tissue diseases when faced with recurrent wounds and to search for additional symptoms that might yield the underlying diagnosis.
Conclusion
Pediatric leg ulcers are a relatively uncommon phenomenon; however, the etiologies are vastly different than adult leg ulcers and require careful contemplation surrounding the cardinal etiology. The main categories of disease in pediatric leg ulcers after trauma include hematologic abnormalities, infection, genodermatoses, and autoimmune diseases. The evaluation requires obtaining a thorough history and physical examination, including pertinent family histories for associated inheritable disorders. If the clinical picture remains elusive and the ulceration fails conservative management, a biopsy with tissue culture may be necessary to rule out an infectious etiology.