ANSWERS
CASE 59: SHORTNESS OF BREATH AND HEARTBURN
A 52-year-old gentleman presents to his GP complaining of shortness of breath on exertion and fatigue, which has been worsening for the past 3 months. During a systemic enquiry, the patient reveals that his previously uninvestigated heartburn and indigestion have recently become increasingly bothersome, especially at night. This is unabated by over-the-counter antacids. The patient also admits to using regular ibuprofen for long-term knee pain. He denies any change in weight, bowel habit or appetite. He has drunk 30 units of alcohol per week for the past 20 years, but does not smoke. He attributes his symptoms to the stress caused by looking after his disabled son.
Examination
The patient is apyrexial but looks pale. His heart rate is 90, regular rhythm. The GP also notes angular stomatitis. Examinations of his cardiorespiratory and abdominal systems are unremarkable.
INVESTIGATIONS
Haemoglobin 101
White cell count 7.1
Red cell count 6.0
Platelets 500
Mean corpuscular volume 75
Mean cell haemoglobin 20
Thyroid-stimulating hormone 2 Iron profile
Serum iron 9
Serum ferritin 10
Total iron binding capacity 77
Transferrin saturation 10%
B12 and folate levels both were normal.
Urinalysis: Negative for blood, protein, and glucose.
Peripheral blood film shows hypochromic microcytic cells and pencil-shaped poikilocytes.
QUESTIONS
1. What is the most likely diagnosis?
2. What further investigations would you arrange?
3. Would you arrange a blood transfusion for this patient?
DOI: 10.1201/9781003242697-62 157
100 Cases in Clinical Pathology and Laboratory Medicine 158
ANSWERS
This patient’s haematological indices suggest anaemia (low haemoglobin level), with micro
cytic red cells demonstrating low MCV (reflecting reduced average red cell size) and MCH (reduced number of haemoglobin molecules per red cell).
The iron profile suggests a deficiency of serum iron, associated with a reduction in the amount of iron storage (ferritin) and an increase in the body’s attempts to bind to serum iron (TIBC).
Both serum iron and ferritin levels are affected by other conditions—for example, ferritin increases with liver disease and infection. Hence, unless the patient does not have any other pathology, their levels may not give an accurate assessment of the iron status in the body.
Haematologists tend to rely more on transferrin saturation for giving an accurate assessment.
Usually the body absorbs less than 10% of dietary iron via the duodenum. Absorption is impaired by tea and alkaline foods such as vegetables. During deficiency, an increase in iron absorption is concomitant with a rise in transferrin, which acts to carry iron to developing red cells in the bone marrow. A high level of transferrin distinguishes iron deficiency from other causes of anaemia.
The peripheral blood smear shows hypochromic (pale) red blood cells. There are also long, pencil-shaped red cells, typically seen in iron deficiency. All of these features point towards iron deficiency as a cause of this man’s anaemia. The raised platelet count is also a recognised feature of iron-deficiency anaemia.
A differential diagnosis would include beta thalassaemia trait because this also produces anaemia with low MCV. Usually beta thalassaemia trait would demonstrate raised haemo
globin A2 (HbA2). Sideroblastic anaemia can present with microcytic, normocytic, or mac
rocytic anaemia. However, the levels of iron and ferritin may be raised, with a normal TIBC.
Bone marrow biopsy would demonstrate ring sideroblasts, which are erythroblasts in which the nucleus is encircled by rings of mitochondria containing iron deposits.
Iron deficiency is the most common cause of anaemia worldwide. It takes several years for dietary deficiency of iron to manifest. The more common causes are chronic blood loss from the heavy menstrual bleeding in women and bleeding from the gastrointestinal system in men and women. Iron can also be lost through the skin, as seen in exfoliative dermatitis.
Other causes include increased demand for iron as seen in newborns, adolescents and preg
nant and lactating women. Gluten enteropathy and a gastrectomy can also predispose to iron deficiency.
Occasionally patients (usually children) with iron deficiency will exhibit pica, which is an appetite for non-nutritive substances like crushed ice, paper or chalk. This disappears upon correction of iron levels.
Acute blood loss presents with a normochromic normocytic (as opposed to hypochromic microcytic) anaemia and reticulocytosis because plasma volume is able to re-expand over the course of 3–7 days. However there are several clinical indicators of chronic blood loss in this patient’s history. These include worsening heartburn and indigestion, a long-term history of non-steroid anti-inflammatory drug (ibuprofen) use and high alcohol intake. Gastrointestinal (GI) lesions are commonly associated with bleeding and iron deficiency. Further investiga
tions in this patient included both upper GI tract endoscopy and a colonoscopy. This revealed gastritis and a duodenal ulcer. Biopsies showed positivity for Helicobacter pylori infection.
Blood transfusion is not indicated for this patient. Unfortunately, many clinicians tend to rush and give a blood transfusion when it is not indicated. A low haemoglobin level is not on
Case 59: Shortness of Breath and Heartburn 159
its own an indication for blood transfusion. A healthy patient with iron deficiency should be expected to recover his normal haemoglobin levels with adequate iron supplements. Oral fer
rous sulphate is available, and if not tolerated, other products such as ferrous fumarate can be an alternative. If oral iron is not effective, intravenous iron can be given and is usually very effective in treating iron deficiency.
A common threshold for transfusion is a haemoglobin level of 80 g/L or less, but this in itself is not an absolute indication. Young patients with iron deficiency and a haemoglobin level of less than 80 g/L who are not symptomatic are expected to recover well with iron supple
ments. The patient’s symptoms—chest pain or dizziness—and clinical signs—low BP and tachycardia—should be taken into consideration when deciding on whether to give a blood transfusion. (Note: Patients with a history of ischaemic heart disease usually need a higher level of haemoglobin. Therefore, the haemoglobin level may need to be maintained at 100 g/L or higher.)
KEY POINTS
• Iron-deficiency anaemia is commonly caused by dietary deficiencies, but all patients need to be assessed for possible blood loss because of a GI lesion, and if indicated, appropriate investigations should be arranged.
• In practice a low transferrin saturation is a good indicator of iron deficiency in the body.
• Blood transfusion should not be given based on low haemoglobin levels alone:
the patient’s symptoms and signs need to be taken into consideration.