Vitamin B12 deficiency: Complications may include pancytopenia and black tarry stool


The body relies heavily on vitamin B12 for the functioning of the nervous and neurological systems. Without it, the body is in peril of severe complications like anaemia, but even deadlier problems have been reported. In instances where blood cells become affected, some patients develop the “life-threatening” condition known as pancytopenia.

In 2020, the Journal Karger outlined the case of a 48-year-old male who presented to an emergency room after suffering a week-long battle with progressively worsening symptoms.

The report states that the 48-year-old gentleman […] presented with a one-week history of dizziness and upper gastrointestinal bleeding.

His chief complaints were dizziness upon standing and tar-like stool, also known as melena.

Subsequent laboratory evaluations revealed pancytopenia and “severely reduced B12 levels”, among several other anomalies.

READ MORE: Man ‘confined to his home’ after B12 deficiency compromises his limbs

Despite being a chronic tobacco chewer for 20 years, the patient’s medical history did not stand out to doctors.

The presence of pancytopenia is a rare and peculiar manifestation of vitamin B12 deficiency.

It can result from several factors including non-steroidal anti-inflammatory drugs, infections and aplastic anaemia.

However, “severe pancytopenia […] occurs in some patients with severe B12 deficiency in addition to megaloblastic anaemia,” according to the patient’s report.


In pancytopenia, the body has too few red blood cells, white blood cells and platelets.

According to St Jude Children’s Research Hospital, this can lead to life-threatening symptoms that affect the entire body if left untreated.

This is because as blood platelets become affected, excess bleeding and an increased risk for infection are more likely.

Such complications usually occur when the body is faced with an oxygen shortage or immune system problems.

READ MORE: Man, 55, loses brain cells due to vitamin B12 deficiency

Symptoms like black and foul-smelling faeces occur when bleeding has happened in the gastrointestinal tract.

Upon examination, a patient with pancytopenia may also display signs of an enlarged spleen, accelerated heart rate and swollen lymph nodes.

How to avoid pancytopenia?

Pancytopenia can occur in cases of severe vitamin B12 deficits that are sustained over time.

Once in the liver, stores of vitamin B12 are generally large enough to supply adequate levels for over five years.

Eating sufficient amounts of vitamin B12-rich foods should therefore offset any complications.

If levels of the nutrients aren’t sustained, symptoms like glossitis, neuropathy and cognitive dysfunction are bound to appear before pancytopenia.

Classically, the neuropathy in vitamin B12 deficiency manifests as symmetric paraesthesias, numbness or problems with ambulation. The legs also tend to be affected before the arms.

If an individual’s vitamin B12 deficiency is caused by malabsorption, however, patients may require vitamin B12 infections or supplementation for support.



Read original article here

Denial of responsibility! TechnoCodex is an automatic aggregator of the all world’s media. In each content, the hyperlink to the primary source is specified. All trademarks belong to their rightful owners, all materials to their authors. If you are the owner of the content and do not want us to publish your materials, please contact us by email – [email protected]. The content will be deleted within 24 hours.

Leave a comment