I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
This is indicative of anemia. This means that your oxygen carrying capacity of the blood is decreased. This can occur due to various reason like low iron levels, B12 deficiency, inadequate absorption of iron or protein etc.
A colonoscopy is usually advised as there can be polyps in the intestines (benign growths) which can bleed intermittently and can cause anemia. Ferritin is a blood test which evaluates for the total iron available in the body. Serum ferritin is the most useful test for diagnosing iron-deficiency anemia. Low serum ferritin (less than 12 ng/mL) is highly specific for iron-deficiency anemia. Please read this resource;
The most common causes are;
1) iron deficiency (with or without blood loss),
2) chronic disease/inflammation
3) chronic kidney disease
4) deficiencies of folate or vitamin B-12,
5) diseases of the bone marrow
6) hypothyroidism, hypersplenism, and hemolytic anemia
So investigations entail;
1) Complete blood count (CBC) which has been done for you already.
2) Peripheral blood film
3) Vitamin B-12
5) Reticulocyte count
7) Thyroid-stimulating hormone
8) Serum creatinine and estimated glomerular filtration rate
9) Serum ferritin
10) Serum iron
11) Total iron-binding capacity
So these investigations need to be done for the exact assessment and long term management.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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