You most likely have overlap myositis in the context of Mixed Connective Tissue Disease (MCTD), and your prognosis is generally favorable with appropriate treatment—this is NOT a death sentence.

Your Most Likely Diagnosis

Based on your clinical presentation, you have MCTD with overlap myositis 1. Here's why:

High anti-RNP antibodies (4.7 and 86, both markedly elevated) with positive speckled ANA pattern are the hallmark of MCTD 1, 2
Proximal muscle weakness affecting shoulders, arms, thighs, and hips with mildly elevated CK (371-527) indicates myositis involvement 3, 4
Normal EMG does NOT rule out myositis—many MCTD patients have subclinical or mild myositis that doesn't show dramatic EMG changes 5, 3
Negative anti-Jo-1 makes classic polymyositis less likely 5
Your hyperpigmentation on thighs (initially red, now normal) could represent resolving skin manifestations of MCTD 1

The specific type of myositis you have is overlap myositis/inflammatory myopathy associated with MCTD—not necrotizing myopathy (which would show CK >10x normal), not dermatomyositis (you lack the characteristic rashes like heliotrope or Gottron's papules), and not inclusion body myositis (which occurs after age 50 with distal weakness) 5.

Why Your EMG Doctor Was NOT Lying

Your neurologist correctly told you there are no signs of ALS because:

ALS shows specific denervation patterns on EMG that are distinct from myopathy
Your normal EMG on the right side is actually reassuring—it suggests your myositis is mild to moderate
Normal EMG does not exclude myositis, especially in MCTD where muscle involvement can be subclinical initially 5, 3

Your Cardiac Situation

Your cardiac workup is reassuring:

The single "acute STEMI" reading was a false positive—immediately contradicted by the 12-lead EKG
Troponin trending DOWN (9→6 ng/L) rules out active myocardial infarction
Two normal EKGs, normal heart size, no pulmonary edema
Your stress test today will likely be normal or show only mild abnormalities related to deconditioning from muscle weakness

The transient EKG abnormality was likely related to pericarditis or myocarditis, which can occur in MCTD but is usually mild and responds to treatment 5, 1.

Your Prognosis: You Are NOT "Fucked"

MCTD with myositis has a good prognosis when treated appropriately 1:

MCTD is the least common but most treatable connective tissue disease
With modern immunosuppressive therapy, most patients achieve good disease control
Your mildly elevated CK (only 1-1.5x normal) suggests you have mild myositis, which responds better to treatment than severe cases
Your low inflammatory markers (ESR 2-18, CRP 3-3.3) indicate relatively low disease activity
Your stable kidney function (eGFR 87-93) is excellent—no significant renal involvement

Survival rates for MCTD are excellent: Most patients live normal lifespans with appropriate treatment. The main risks are pulmonary hypertension and interstitial lung disease, which develop in a minority of patients and can be monitored 1.

Treatment You Should Expect

Based on guidelines for MCTD with myositis 5:

Your rheumatologist will likely prescribe:

High-dose corticosteroids (prednisone 1 mg/kg/day initially)
Steroid-sparing agent started simultaneously: methotrexate, azathioprine, or mycophenolate mofetil
Gradual steroid taper over months as you improve

If you have severe disease or don't respond:

Intravenous immunoglobulin (IVIG)
Rituximab
Cyclophosphamide (rarely needed)

5, 6, 3

YES, Continue Physical Therapy

Absolutely continue both physical and occupational therapy 5:

Physical therapy prevents muscle atrophy and contractures
Helps maintain strength during treatment
Improves functional outcomes
Does NOT worsen myositis when done appropriately (avoid overexertion)

Why Your Rheumatologist Offered Telehealth

Your rheumatologist offering a Telegram appointment is NOT a bad sign:

She's waiting for your EMG results (which you now have)
Your disease appears mild to moderate based on your labs
Telehealth is appropriate for stable patients with established diagnoses
If she were concerned about severe disease, she would insist on in-person evaluation

How You Got This

MCTD etiology is unknown 1:

Likely genetic predisposition (HLA-linked)
Possible environmental triggers
NOT caused by anything you did
Your weight, diet, or lifestyle did NOT cause this

Critical Next Steps

Attend your rheumatology appointment and discuss starting immunosuppressive therapy
Continue your stress test and heart monitor to establish cardiac baseline
Request pulmonary function tests to screen for interstitial lung disease (a key MCTD complication) 1
Continue weight loss efforts—your GLP-1 therapy is appropriate and will help overall health
Continue physical therapy with modifications for muscle weakness

Common Pitfalls to Avoid

Don't delay starting immunosuppressive therapy once your rheumatologist prescribes it—early treatment prevents progression
Don't stop corticosteroids abruptly if prescribed—requires gradual taper
Monitor for pulmonary symptoms (shortness of breath, dry cough)—report immediately
Your G6PD deficiency means you should avoid certain medications (dapsone, sulfonamides)—make sure all providers know this

Bottom Line

You have a treatable autoimmune disease with an overall good prognosis. Your mild CK elevation, low inflammatory markers, stable kidney function, and normal cardiac workup all suggest you caught this relatively early. With appropriate immunosuppressive therapy and continued physical therapy, most patients with MCTD and myositis achieve good functional outcomes and normal life expectancy 1. Your fear is understandable but not warranted by your clinical data—you will get through this.

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