Dr.Akshay Kishore , Dr.Suma Balan (Paed Rheumato),Dr.C.Jayakumar
AIMS KOCHI
Eleven year old female child presented with edema of hands and feet since April 2023. She had pain in several joints of the hands and feet and in the Tempero mandibular joint. Pain and swelling were more in the morning hours .She also had weight loss and fatigue. History of lower back ache also present.
No history of recurrent oral ulcers , breathlessness , blurring of vision , dry eyes or contact with people having Kochs
Her grandmother was suffering from rheumatoid arthritis.
On examination , there was salt and pepper pigmentation on the nape of neck along with puffy fingers. Hyperpigmentation noted in hands /neck region.
There was no pallor or lymphadenopathy.
There is swelling of fingers. TMJ tenderness along with restricted mouth opening present. She has difficulty in getting up from squatting position. Gait is normal.
Differential diagnosis considered were :
1. Mixed connective tissue disorder (MCTD)
2. Systemic sclerosis with overlap syndrome.
Labs TC-9010 , N-55% , L-32% , HB -13.7 , PLT- 397000 , CRP-4.3 , ESR -100 , rheumatoid factor – 68.
ANA – IFA – 4 + with ANA blot showing U1RNP /Sm strong positive.
Pulmonary function test – normal.
ECHO – normal
With the symptoms and signs such as proximal myalgia , weight loss , puffy fingers , salt and pepper pigmentation and inflammatory arthritis along with above laboratory findings , a diagnosis of MCTD was made.
She was started on Methotrexate and steroids.
Discussion : Mixed connective tissue disease (MCTD) is a rare systemic autoimmune disease with an overlapping feature of at least two connective tissue diseases (CTD), including systemic lupus erythematosus (SLE), systemic sclerosis (SSc), polymyositis (PM), dermatomyositis (DM) and rheumatoid arthritis (RA) along with the presence of a distinctive antibody, anti-U1-ribonucleoprotein (RNP) previously known as an antibody to extractable nuclear antigen (ENA).
Pulmonary involvement occurs in almost 73% of patients, and dyspnea is the most common symptom.
Pericarditis is the most common variant of cardiac disease involving up to 40% of patients.
In renal , most common is membranous nephropathy. Immunological markers include high titer speckled pattern anti-nuclear antibody , high titer anti-U1-RNP, and anti-U1 70kd antibody. Data shows that 65% of patients with MCTD have positive rheumatoid factor, and 50% of patients have positive anti-CCP. Xray of affected joints might reveal small, asymmetrical periarticular erosions. Echocardiogram shows Pericardial effusion, mitral valve prolapse, left ventricular hypertrophy, and changes secondary to pulmonary hypertension.
Arthritis and arthralgia usually respond to NSAIDs and hydroxychloroquine. For refractory synovitis, corticosteroids and methotrexate can be used.
Pleuritis, pericarditis, myositis, myocarditis, and aseptic meningitis usually respond to steroids. Steroid-sparing agents, e.g., methotrexate, cyclosporine, azathioprine, and mycophenolate mofetil, are commonly used as second-line agents.
Take home message :
Think beyond Rheumatoid arthritis and SLE when the joints are involved and no need to be scary about steroid and methotrexate when we come across rheumatoid problems even in children