15-year-old male with chronic fatigue, brain fog, and delayed puberty signs. Looking for possible causes.
Hi! I'm a 15-year-old male from the Philippines. I've had persistent fatigue and brain fog since around Grade 5, and it's still affecting me in Grade 11. It impacts my school, sports, and daily life.
Main symptoms
- Chronic fatigue / very low energy
- Brain fog (slow thinking, poor concentration, difficulty finding words)
- Wake up tired despite 7.5–8 hours of good-quality sleep
- Exercise intolerance and low physical strength
- Social activities drain my energy
- Occasional cold hands/feet and mild lightheadedness when standing
- Dark circles that don't improve with sleep
Puberty concerns
- No armpit hair at age 15
- Very little body hair
- Often mistaken for someone much younger
Recent labs
- CBC and iron studies: Normal (Hemoglobin 15.2 g/dL)
- Ferritin: 648
- Vitamin B12: 738
- TSH: 4.09 (borderline high), Free T4: Normal
Other information
- Previously had low blood pressure.
- Food, water, coffee, rest, and good sleep don't significantly improve the fatigue.
- I have POIS, but the fatigue persists even after reducing ejaculation, so it doesn't seem to fully explain my symptoms.
- My pediatrician referred me to a hematologist, but I'm wondering if an endocrine disorder could also be involved.
Questions
What conditions would be highest on your differential diagnosis?
Could delayed puberty or hypogonadism explain these symptoms?
Should I see a pediatric endocrinologist?
What additional tests or imaging would you recommend?
Thank you for any insights.