Paediatrics Marrow Pg 221-230 (Peadiatric Rheumatology)

Solid Tumors in Children - COG Staging

• Stage 1: Tumor limited to kidney, completely resectable.
• Stage 2: Tumor extends beyond kidney, completely resectable, no lymph node involvement. Residual tumor confined to abdomen.
• Stage 3: Tumor metastasized to regional lymph nodes, extending into IVC.
• Stage 4: Tumor metastasized to lymph nodes outside abdomen and distant organs like lungs and liver.
• Stage 5: Bilateral kidney involvement.

Solid Tumors in Children - Treatment

• Stages 1-4: Radical or partial nephrectomy.
• Stage 3/4: Chemotherapy (Vincristine + Actinomycin D) for 18 weeks, surgery + chemotherapy + radiotherapy.
• Stages 1/2: Chemotherapy (Vincristine + Actinomycin D + Doxorubicin) for 24 weeks and radiotherapy.
• Stage 5: Surgery + chemotherapy + radiotherapy.

Juvenile Dermatomyositis (JDM)

• A multisystem disorder involving skin and muscles, possibly with systemic vasculopathy, affecting children aged 5-14 (females more than males).
• Proximal, symmetrical muscle weakness affecting shoulders and hips, causing difficulties with getting up and climbing stairs.
• Skin features include violaceous discoloration, red scaly lesions over extensor aspects of joints, periorbital edema, heliotrope rash, Gottron papules, and shawl sign.
• Nail findings include periungual erythema and dilated nail fold capillaries on nail fold capillaroscopy.

Wilms' Tumor

• Unilateral kidney tumor, also known as nephroblastoma, most common solid kidney tumor in children.
• Second most common intra-abdominal tumor in children, originating from undifferentiated mesenchyme of the kidney.
• Most common in children aged 2-5 years.
• Risk factors include malformations like horseshoe kidney, cryptorchidism, and hypospadias.
• Genetic syndromes associated include WAGR syndrome with WT-1 gene mutation and Beckwith-Wiedemann syndrome with WT-2 gene mutation.
• Clinical features include asymptomatic abdominal mass in the loin, hypertension, and hematuria.
• Most common site of metastasis is lung, followed by lymph nodes and liver.
• Localized tumors are treated with surgical resection, while disseminated tumors require surgery + chemotherapy, and radiotherapy if chemotherapy is ineffective.
• Autologous hematopoietic stem cell transplant (AHSCT) is an alternative treatment option.

Enthesitis-related Arthritis

• More common in males.
• Characterized by inflammation of tendons and ligaments, asymmetrical arthritis of lower limbs, and HLA-B27 association.
• Potential feature of sacroiliitis, which is a precursor to ankylosing spondylitis.

Juvenile Idiopathic Arthritis (JIA)

• Most common chronic rheumatic arthritis in children, an autoimmune disorder.
• Affecting children under 16 years with involvement of at least one joint for a duration of at least 6 weeks.
• Other conditions are excluded.
• Types include Oligoarticular JIA (most common, affecting≤4 joints, large joints like knee, ankle, wrist), Polyarticular JIA, and Systemic JIA.

Langerhans Cell Histiocytosis (LCH)

• Spectrum of LCH varies based on age and clinical features.
• Eosinophilic granuloma - older children, lytic bone in skull.
• Hand-Schüller-Christian disease - 2-6 years, skull defect, exophthalmos.
• Letterer-Siwe disease - <2 years, seborrheic dermatitis, ear discharge, systemic involvement: Hepatosplenomegaly (Abnormal LFT), Lymphadenopathy.
• Diagnosis is confirmed by Immunohistochemistry (CDla, CD207), biopsy, and electron microscopy.
• Treatment depends on the severity of the lesion and might include curettage, intralesional steroids, Vinblastine, 6-MP, prednisolone, and Cladribine.

Neuroblastoma

• Most common intra-abdominal tumor in children, second most common extracranial solid tumor.
• Common malignancy in infancy, originating from neuroblasts derived from neural crest cells.
• Primary sites of involvement include the adrenal gland and paravertebral sympathetic chain.
• Secondary sites include the posterior mediastinum and pelvis.
• Grossly, it appears as a solid tumor, microscopically - small, uniform blue cells with scant cytoplasm and hyperchromatic nuclei.
• Homer-Wright rosettes have a rose petal-like appearance.
• Clinical features include abdominal mass, constitutional symptoms, Horner's syndrome, heterochromia iridis, and metastasis features such as bone pain, peri-orbital swelling, and blueberry muffin lesions.

Henoch-Schönlein Purpura (HSP)/IgA Vasculitis

• A multisystem small vessel vasculitis, common in children (age 4-8 years).
• Pathogenesis involves leukocytoclastic vasculitis, fibrinoid necrosis, and IgA deposits.
• Characterized by palpable purpura, non-blanching and non-thrombocytopenic, typically located in dependent areas like lower limbs and genital area.
• Other features include abdominal pain, joint involvement, and renal involvement including hematuria/nephritis and nephrotic range proteinuria.

Paediatric Rheumatology: Polyarticular JIA

• Rheumatoid Factor Positive Polyarticular JIA affects any age up to 16 years, predominantly occurring between 9-11 years.
• Joints affected include knee, hip, wrist, metacarpophalangeal, proximal interphalangeal, cervical spine, and temporomandibular joint.
• The disease is symmetrical, associated with rheumatoid nodules and uveitis.

Paediatric Rheumatology: Systemic JIA

• More common in males.
• Characterized by daily fever spikes, arthritis, and any one of the following features: Salmon-colored non-pruritic maculopapular rash, hepatosplenomegaly, lymphadenopathy, serositis (pleuritis/pericarditis), Koebner phenomenon, and hypersensitivity reactions.
• Complication: macrophage activation syndrome (MAS) - a hyperinflammatory condition with continuous fever, drop in cell counts predominantly thrombocytopenia, elevated ferritin and triglycerides, and hemophagocytosis on bone marrow biopsy.

Paediatric Rheumatology: Psoriatic Arthritis

• More common in females.
• Characterized by arthritis and psoriasis or any two of the following: nail pitting, dactylitis (sausage digits), or a first-degree relative with psoriasis.

This quiz covers staging and treatment options for solid tumors in children, including nephrectomy and chemotherapy regimens for various stages. In addition, it addresses juvenile dermatomyositis, a multisystem disorder affecting young children. Test your knowledge on these critical pediatric conditions.