Discussion
Thiamin functions as a coenzyme in the metabolism of carbohydrates and
branched-chain amino acids. It is vital for two types of reactions in
human body; decarboxylation of α-ketoacids and transketolation. Thiamin
has not been linked to toxicity.1 With limited body
storage, Thiamine deficiency can occur in as short as 14
days.2
Thiamin deficiency can present as Beriberi in its two types wet and dry,
or the Wernicke-Korsakoff syndrome. Dry Beriberi present as
symmetrical sensory and motor peripheral neuropathy. Wet type mainly has
cardiac involvement with cardiomyopathy.1 presentation
can be as severe as multiorgan failure.3
Nowadays this disease is uncommon in developed countries. Most cases
seen are related to patients who underwent bariatric surgeries or who
suffer from alcoholism and severe malnutrition.4–6Thiamin deficiency has been described in patients on total parenteral
nutrition (TPN) if adequate vitamin replacement is not
provided.7
Cardiac Beriberi can be a challenging diagnosis for patients presenting
with dilated cardiomyopathy. The diagnosis can be made based on clinical
signs and symptoms associated with dilated cardiomyopathy, peripheral
neuropathy, malnutrition and absence of other with response to Thiamin
supplementation.8
Thiamin plays an integral role in TCA cycle. Its deficiency leads to
Adenosine accumulation and decreased ATP production. This can be seen in
Beriberi heart disease. It can be chronic which starts as high output
state secondary to peripheral vasodilation and decreased vascular
resistance. If this state continues along with decreased myocardial
contractility, it can lead to low output state.8–12Acute Beriberi (Shoshin beriberi) can present with low cardiac output
and even cardiogenic shock. This deficiency can lead to myonecrosis
which was described in two autopsy studies13Aggressive
repletion of thiamine results in dramatic improvement in systolic heart
function8,11,14, this was also seen in our patient.
In our review in literature, we didn’t find any cases where Thiamin was
linked to rhabdomyolysis. Suspected mechanism likely similar to
cardiomyopathy. Dramatic improvement in total CK level along with
improved energy level and decreased calf tenderness clinically support
this theory.
In conclusion, patients presenting with rhabdomyolysis and signs of
heart failure who are malnourished might be experiencing Beriberi
disease. Thiamin, water soluble vitamin, is not associated with
toxicity. Aggressive replacement of Thiamin should be attempted given
dramatic improvement if this is the etiology.