Fernando Pérez Jacobo

Hematologist interested in lymphoid malignancies | Metalhead | Sci-Fi nerd | 🇲🇽 |🩸 🔬 🪐 🤘🏼|

[Keith Siau @drkeithsiau]

The flagella of Helicobacter pylori work like specialised propellers driven by a high-torque rotating motor. These convert chemical energy generated from proton gradients across the bacterial membrane into mechanical rotation. These help the bacteria to navigate the thick mucus of the human stomach to travel from highly acidic areas (pH 2) to areas with a more neutral pH (pH 5.5 to 7.5) where they thrive best.

Using high-resolution electron microscopy imaging, scientists have recently characterised the architecture of this motor which form the building block of flagella, and my god, does this look like a beautiful feat of engineering. 🦠⚙️

[Nicolas Duployez @NicolasDuployez]

Read the cell, guess the genetics.
#HemePath #Genetics #leusm #AMLsm 🔬🧬🩸

[Dr. José A. Queizán Hernández @queizan]

Se cumplen 50 años de la publicación original del esquema #ABVD para el tratamiento de 1ª línea del #LinfomadeHodgkin “Combination chemotherapy of Hodgkin's disease with adriamycin, bleomycin, vinblastine, and imidazole carboxamide versus MOPP” Bonadonna et al Cancer1975;36:252-9

[Dr. Chokri Ben Lamine @abouabdrahman0]

💊 Hydroxyurea in Acute Myeloid Leukemia (AML) – Comprehensive Review 🩸

Hydroxyurea (HU) is a ribonucleotide reductase inhibitor used primarily in chronic myeloid disorders, but it also plays a role in AML, especially for cytoreduction in hyperleukocytosis or blast crisis.

📌 Indications in AML

1️⃣ Cytoreduction in Hyperleukocytosis (>100K WBCs) 🚨
•Prevents leukostasis (dyspnea, CNS symptoms, ischemia) 🛑
•Used before definitive AML therapy (e.g., induction chemotherapy)

2️⃣ Palliative Treatment in Elderly/Unfit AML Patients ♿
•For patients ineligible for intensive chemotherapy
•Slows leukemic progression in non-transplant candidates

💊 Dosing

🔹 Initial: 50–100 mg/kg/day PO (divided doses)
🔹 Titration: Adjust based on WBC response
🔹 Goal: Reduce WBCs <50K before starting induction 💉

⏳ How Long to Use?
•Stop once WBC goal is achieved OR AML induction starts
•Can be tapered if cytoreduction is no longer needed

⚠️ Side Effects

🔹 Myelosuppression (Dose-limiting) 🩸
•Neutropenia (ANC <1.5K)
•Thrombocytopenia (PLT <100K)
🔹 Mucositis & GI Toxicity 🤢
•Nausea, diarrhea, oral ulcers
🔹 Dermatologic 🚨
•Skin hyperpigmentation, leg ulcers, nail changes
🔹 Renal & Hepatic Effects (Rare)
•Monitor LFTs & Cr in prolonged use

🚫 Contraindications

❌ Severe Bone Marrow Suppression (ANC <500, PLT <50K)
❌ Pregnancy (Teratogenic – Avoid in 1st Trimester!) 🤰🚨
❌ Severe Renal or Hepatic Dysfunction
❌ Active, Uncontrolled Infection 🦠

📉 When to Stop or Decrease the Dose?

🔹 ANC <500 or PLT <50K → Hold HU, resume at lower dose 🛑
🔹 Severe GI toxicity (persistent N/V/D) → Decrease dose 💊
🔹 Severe skin ulceration or intolerance → Discontinue

📝 Key Takeaways

✅ Hydroxyurea is a TEMPORARY bridge in AML hyperleukocytosis
✅ Monitor CBC every 1–3 days during use 🩸
✅ Not curative, only cytoreductive or palliative
✅ Discontinue before definitive AML therapy

#AML #Leukostasis #Hydroxyurea #HemeOnc #Cytoreduction

[Rina Michaus @RinaMichaus]

Great presentation about Castleman disease! @AaronGoodman33 #AMEH2024

[Glen O'Humeral @HumeralO]

When the INR is greater than the hemoglobin

[James Lucas @JamesLucasIT]

Solar Eclipse 2024 - a thread 🧵

1. Cleveland by Gabe Wasylko

[Ahmed Kotb @AhmedKo45911157]

✔️Wonderful summarised algorithm for Lymphoma Classification
#lymphoma #classification #NHL

[Fernando Pérez Jacobo @hemetalogist]

@hematologo Linfatortuga adolescente mutante

[Fernando Pérez Jacobo @hemetalogist]

🐢

[Fernando Pérez Jacobo @hemetalogist]

Gran hilo sobre esplenomegalia en HTP!

[Tony Breu @tony_breu]

1/15
🤔Why does portal hypertension lead to splenomegaly.

I also assumed the spleen became "congested" from backflow of blood.

Turns out, it isn't that simple. And there are interesting therapeutic implications.

Let's have a look.

[𝗡𝗶𝗵𝗮𝗿 𝗗𝗲𝘀𝗮𝗶 MD, DM @nihardesai7]

Consulting #hematology for a platelet count of 149k 🤷‍♂️

#MedTwitter

[Mar Gómez @MarGomezH]

Bienvenidos al Punto Nemo: así es el lugar más alejado de tierra firme del mundo 🌍

El Punto Nemo es tan remoto, que los humanos más cercanos a él son los astronautas de la Estación Espacial Internacional.Pero, además de esto,este lugar alberga grandes curiosidades. ¡Abro hilo!

[Amer Zeidan عامر زيدان @Dr_AmerZeidan]

A smart hematologist spot diagnosis!

[Fernando Pérez Jacobo @hemetalogist]

Gran hilo! 🦈

[William Aird @WilliamAird4]

AN APPROACH TO MACROCYTOSIS

[Fernando Pérez Jacobo @hemetalogist]

Un mini-hilo de hemato-paleontología 🦖 🤯

[William Aird @WilliamAird4]

1/3

DINOSAUR RBCs

Dinosaur fossils generally lack soft tissues, including blood cells. However, recent studies have shown that such material may be preserved over tens of millions of years depending on the preservational environment (e.g., within carbonate concretions).

[Tony Breu @tony_breu]

1/13
🤔Why does smoking cause leukocytosis?

I see this with some frequency but haven't taken to time to understand the mechanism.

Let's have a look.

[Lidia Aurora Mondragón Posadas @DraLidiaGeria]

Se busca
Médic@ Geriatra con
Título, Cédula y Certificación del consejo.
Para laborar en pequeño hospital privado/beneficencia zona Periférico- Tacubaya. Matutino L-V 9-3 pm por honorarios, emitir facturas.
Interesados mandar CV al correo
[email protected]

[William Aird @WilliamAird4]

1/10

CASE

76 yo M with Waldenstrom's macroglobulinemia (WM; IgM 3000-5000 mg/dL), treated in past with rituximab, dexamethasone and cytoxan, presents with iron deficiency anemia. Colonoscopy and OGD negative. Capsule study shows multiple jejunal AVMs.

Ring any bells?