QSP Newsletter

QSP Newsletter 33 - Essential Thrombocythemia, Iron Deficiency

February 2023

Monthly Digital Case Study
February 2023 QSP Slides
Iron Deficiency
(PDF for print)

Monthly Digital Case Study

February 2023 QSP Slide 4:


Field from RBC section showing numerous platelets, a large platelet and RBC and platelet anisocytosis

FBC Results

WBC 25.9 *(10^3/mm3)
RBC 3.28*(10^6/mm3)
HGB 9.4 (g/dL)
HCT 29.9* (%)
MCV 91 (fL)
MCH 28.5 (pg)
MCHC 31.3 (g/dL)
PLT 2721 (10^3/mm3)

Neutrophils 58.8%
Lymphocytes 29.1%
Monocytes 7.7%
Eosinophils 2.6%
Basophils 0.9%
Myelocytes 0.9%
Large Platelets 13

Clinical Details

Female aged 63
Transient ischemic manifestations.

Slide Information

Diagnosis of Essential Thrombocythemia (Cytogenetics: absence of ph chromosome or BCR-ABL rearrangement). Molecular biology: Janus kinase 2 (Jak2) mutation? Anisocytosis and platelet anisocytosis.

Expert Comment

Appearance of SMP; Either Essential Thrombocythemia (ET) or CML, but the presence of large platelets would suggest ET.

February 2023 QSP Slides

► Nothing to report

► Macroplatelets

► Hematology Unit, Atypical Lymphocytes. Lymphoma like lymphocytes? NHL

► See case study above

► Eosinophilia

► Leukocytosis

Iron Deficiency

Iron is a trace element that is essential for numerous cellular metabolic functions. As iron is toxic, the body must have  tight regulation of iron absorption to avoid iron deficiency or iron overload.

In a normal 70kg person, the body iron content is 3.5-4g in females and 4-5g in males. Most of the iron is distributed as follows: 65% in the form of hemoglobin (2300mg), 15% in myoglobin and enzymes, 20% in iron stores and only 1-2% bound to Transferrin. Iron is stored as Ferritin complexes contained in every cell but most commonly in the bone marrow, liver and spleen.

A normal western diet contains approx. 7mg of iron / 1000kCal, only 1-2 mg is normally absorbed each day. Dietary iron is in 2 forms: heme iron (10%) and non heme (90%). Heme iron is found in foods from animals (red meat, chicken, fish). 15%-20% of heme iron is absorbed. Non heme or inorganic iron is found in foods of plant origin, cereals and some foods of animal origin e.g. milk and eggs. Less than 5% of non heme iron is absorbed. Heme is taken up directly by interstitial cells by a process called endocytosis and is the most easily absorbed form of iron. Once in the circulation, iron is bound to Transferrin and transported to the bone marrow for hemoglobin synthesis and incorporation into red cells. The body is able to increase the intestinal iron absorption dependant on the bodies iron requirement.

About 120 days after the red cells enter the circulation, senescent red cells are phagocytized by macrophages in the spleen, liver or bone marrow, and the iron is released to be re used. Recycling of heme iron from senescent red cells is the primary source of iron for erythropoiesis and accounts for delivery of 40-60 mg/day. Some of the recycled iron is stored as ferritin and hemosiderin while the majority of it is released via ferroprotein into the plasma bound to transferrin. Approximately 1-2 mg of iron is lost each day as a result of sloughing of cells. In women, approx. 0.006mg iron/day/kg is lost during normal menstruation. Note that the normal amount lost equals the amount taken in by dietary forms of iron, therefore any imbalance will lead to iron depletion.

Iron deficiency can be caused by either failure to absorb sufficient iron (low dietary intake, malabsorption) or chronic blood loss (from genitourinary, gynecological, gastrointestinal tract). Iron deficiency is a worldwide problem, particularly in underdeveloped countries with an estimated frequency of 30% of the global population. Iron deficiency anemia is the most common anemia.

Iron deficiency develops slowly and can be defined in 3 stages (depletion of stores, iron deficient erythropoiesis, iron deficient anemia) which progress unless the iron status is returned to normal, either by increase of iron uptake or cessation of chronic blood loss. The classical microcytic hypochromic RBC picture is only seen in the iron deficiency anemia stage, therefore tests for iron status are crucial in detecting iron deficiency prior to the onset of anemia.

Laboratory tests for iron status include: serum Ferritin iron stores, total iron binding capacity, transferrin saturation, serum iron, and zinc protoporphyrin.

Clinical Picture:

Iron deficiency symptoms are secondary to anemia and include weakness, headaches, irritability, tinnitus and varying degree of fatigue and exercise intolerance, commissural cheilitis (fissures in the corners of the mouth and koilonychia (spoon nails). Some patients may display signs of pica (craving or eating of non food items e.g. clay, soil, or paper). Ice pica is said to be very specific for iron deficiency states. Restless Leg Syndrome may also be seen.

Hematological Abnormalities:

As the iron deficiency progresses, the RDW may increase, indicating the increase in anisocytosis caused by the introduction of smaller red cells (microcytic) into the circulation. Microcytic red cells are produced in the bone marrow due to an extra cellular division before the critical hemoglobin concentration required to stop mitosis is achieved due to the decrease in iron concentration.

Iron deficiency anemia must be considered if the Hb, Hct, and MCV is lower than the normal range for that patient. Morphological changes are not usually marked until the Hb falls below 10-11 g/dL when the characteristic features appear (microcytosis, hypochromasia, anisocytosis, and poikilocytosis). The hypochromic cells often have a large area of central pallor. Target cells may be seen, but if seen in numerous numbers, Hemoglobin C or S trait may be considered. Poikilocytoses include elliptocytes, which may be very thin. These are often referred to as pencil cells.

RBC from Iron Deficiency Patient

RBC from Iron Deficiency Patient

Normal RBC

Normal RBC

The table below shows the laboratory tests in the investigation of iron deficiency:

 NormalIron store depletionIron deficient erythropoeisisIron deficient anemia
Bone marrow iron stores1 - 3 +0 - 1 +00
Serum ferritin mcg/dL50 - 200< 20< 15< 15
TIBC mcg/dL300 - 360> 360> 380> 400
Serum iron g/dL50 - 150 < 50< 30
Seturatiom %30 - 50 < 20< 10
Protophoryn mcg/dL30 - 50 > 100> 200
RBC morphologyNormalNormalNormal




Cell Quiz

What feature is shown in this cell?

A) Pelger-Huet Anomaly
B) Nuetrophil Hypersegmentation
C) Neutro Toxic Granulation

The answer will be displayed in the next QSP Newsletter and on our social media (LinkedIn / Facebook / Twitter).


Last Month’s Quiz Answer

Look at the hematology results below. Which of the slides would fit with these results?

Hb 10.9
WBC 161.1
Platelets 162
Hct 37.1
MCV 110
MCV 110 (fl)
Neutrophil 6.5%
Lymphocyte 93.5%

The Answer:

Slide 1
Monomorphic hyper lymphocytosis associated with numerous naked nuclei. Expert comment: Aspect of CLL.


Iron deficiency anaemia; G. Barragan-Ibanex et al; Rev Med Hosp Gen Méx. 2016;79(2):88---97
Diagnosis and management of iron deficiency anaemia in the 21st century; Teeri D Johnson-Wimb;ey et al; Ther Adv Gastroenterol (2011) 4(3) 177184

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