Faheema Hasan: Chronic Methemoglobinemia Causing Longstanding Tissue Hypoxia and Secondary Erythrocytosis
Faheema Hasan, Associate Professor at United Medicity, shared a post on LinkedIn about a recent article by Naseema Gangat et al, published in American Journal of Hematology, adding:
“Hematology is humbling.
Nothing replaces diligent clinical examination
I recently saw a middle aged male patient referred for evaluation of erythrocytosis.
- Hb 21 g/dL
- TLC 8,900/µL
- Platelets 5 lakh/µL
Peripheral smear otherwise unremarkable.
Marked plethora, no organomegaly.
No smoking, no prior treatment.
The textbook work-up for polycythemia followed:
- EPO greater than 100 mIU/mL (elevated)
- JAK2 — negative
Then further investigations pursued
- SPEP — normal
- ECHO — normal
- Low-dose CT (head/neck, thorax, abdomen) — no pathology
The diagnosis remained elusive.
Because his haematocrit was over 60%, I wanted to re-examine him personally. That second look changed everything.
The patient had deeply pigmented skin. His lips appeared unusually dark, and when I asked further, he said they had looked that way ‘for as long as he could remember’.
As a farmer, his nails were discoloured from years of working with soil — masking another clue.
Cyanosis — that classic grey-blue hue we are trained to recognise — was hidden in plain sight.
I sent an arterial blood gas with methemoglobin estimation.
22% Methemoglobin
Normal: < 1–2%
The final diagnosis:
Chronic methemoglobinemia causing longstanding tissue hypoxia and secondary erythrocytosis.
How and how important and indispensible is clinical examination..
And this paper on Jak negative erythrocytosis is exemplary!!
Work up for cause of possible congenital methemohlobinemia is underway.”
Title: JAK2 Unmutated Erythrocytosis: 2026 Update on Diagnosis and Management
Authors: Naseema Gangat, Natasha Szuber, Ayalew Teffer
Stay updated on an scientific advances with Hemostasis Today.
-
Aug 14, 2026, 23:18Claire Hills: New Paper on Immune Surveillance and Immune Evasion of Senescent Cells
-
Aug 14, 2026, 23:16Are We Overlooking What Matters Most to Women with Von Willebrand Disease? – RPTH Journal
-
Aug 14, 2026, 23:15Markus Müller: A New Base Editing Approach Targeting PCSK9 to Lower Cholesterol Levels
-
Aug 14, 2026, 23:14Chokri Ben Lamine: Avatrombopag in Hematology – Dosing and Monitoring
-
Aug 14, 2026, 23:13Bianca Rocca: PRECISE-DAPT Score Identifies Bleeding Risk After CABG in Patients With POAF
-
Aug 14, 2026, 19:04Ravi Kumar: Why Lupus Anticoagulant Predicts Clots, Not Bleeding
-
Aug 14, 2026, 18:53Veli Bakalov: The Number Every Hematologist Should Know in Polycythemia Vera
-
Aug 14, 2026, 18:41Marta Velia Antonini: Can Nitric Oxide Protect the ECMO Circuit Without Systemic Anticoagulation?
-
Aug 14, 2026, 18:30Irina Gontschar: What the Epkinly FDA Review Teaches Us About Sponsor Oversight