Infantile beriberi is a severe, yet preventable, condition resulting from a deficiency of thiamine, also known as vitamin B1, in infants. This acute disease typically affects infants between one and five months of age. Without prompt intervention, it can lead to serious cardiac complications and can be fatal within a few days.
Understanding Thiamine Deficiency
Infantile beriberi is primarily caused by a severe lack of thiamine. Thiamine plays a role in the body’s energy production, acting as a coenzyme in carbohydrate metabolism. This deficiency leads to impaired energy synthesis within cells.
Thiamine deficiency in infants almost always results from breastfeeding from a mother with inadequate thiamine intake, as breast milk thiamine concentrations depend on her diet. Due to rapid growth, high energy demands, and an accelerated metabolic rate, infants have elevated thiamine requirements relative to their body size, making them particularly susceptible to deficiency in the first year of life. This vulnerability is most pronounced in exclusively breastfed infants of thiamine-deficient mothers.
Recognizing Symptoms and Diagnosis
The clinical manifestations of infantile beriberi can be acute and progress rapidly. Symptoms often appear in infants aged between two and six months. These can include pale skin, hoarseness, diarrhea, vomiting, and weight loss.
Cardiac and circulatory symptoms are common and can be severe. Infants may experience a rapid heart rate (tachycardia), shortness of breath with activity, and swelling of the lower legs (edema). In acute forms, babies can develop dyspnea and cyanosis, which can quickly lead to heart failure.
Neurological signs may also be present, such as incessant crying and a bulging fontanelle. In some cases, infants may exhibit aphonia, where they attempt to cry but produce only faint moans or no sound due to nerve paralysis. Though less common in infantile forms, severe deficiency can also lead to mental confusion or loss of muscle function.
Diagnosis of infantile beriberi typically involves a comprehensive clinical assessment and a detailed dietary history, particularly regarding the mother’s thiamine intake. Doctors may also use laboratory tests to confirm the diagnosis. These tests can include measuring thiamine levels in the blood or assessing erythrocyte transketolase activity. A transketolase activity increase greater than 25% after thiamine pyrophosphate addition indicates severe deficiency, while an increase between 15% and 25% suggests deficiency. Early recognition is paramount due to the rapid progression and potentially fatal nature of the condition.
Treatment and Prevention
Immediate management of infantile beriberi involves prompt thiamine supplementation. This treatment can be administered orally or through injections, leading to rapid clinical improvement, often within hours. Heart function and size can normalize within one or two days following treatment. It is also important to address the thiamine status of the breastfeeding mother, as her deficiency is the root cause for the infant’s condition.
For prevention, ensuring adequate thiamine intake for pregnant and breastfeeding mothers is paramount. The recommended daily intake of thiamine for pregnant and lactating women is approximately 1.4 mg. Dietary recommendations include consuming foods rich in thiamine, such as meat, nuts, seeds, beans, legumes, seafood, and dairy products. Many foods, like bread and breakfast cereals, are also fortified with thiamine.
Research indicates that providing breastfeeding mothers with a daily thiamine supplement, such as 1.2 mg, can achieve healthy thiamine levels in breast milk, thereby preventing infantile beriberi in regions where deficiency is prevalent. Continued nutritional support beyond six months may be beneficial for sustained neurocognitive development in infants.