Suspect thiamine deficiency and obtain a thorough history
A high index of suspicion for thiamine deficiency is essential for diagnosis of WKS. History of alcohol use should be obtained, including quantity, frequency, pattern, duration, and time of last use. Physicians should assess nutrition and ask about vomiting and diarrhea. It is important to collaborate with the patient’s family and friends and inquire into other substance misuse.5
Since WKS targets the dorsomedial thalamus, which is responsible for olfactory processing, patients may complain of a distorted perception of smell.6 On physical examination, look for signs of protein-calorie malnutrition, including cheilitis, glossitis, and bleeding gums; signs of alcohol abuse, such as hepatomegaly; and evidence of injuries or poor self-care.5
Varied presentation leads to under- and misdiagnosis
Diagnosis of WKS can be difficult due to the varied presentation; there is a broad spectrum of clinical features. The clinical triad of mental status change, ophthalmoplegia, and gait ataxia is present in as few as 10% of cases.3 Mental status changes may include a global confusional state ranging from disorientation, apathy, anxiety, fear, and mild memory impairment to pronounced amnesia. Ophthalmoplegia can include nystagmus, ocular palsies, retinal hemorrhages, scotoma, or photophobia; and ataxia can range from a mild gait abnormality to an inability to stand.7 This varied presentation ultimately leads to underdiagnosis and misdiagnosis.
MRI findings are also varied in WKS. However, the mammillary bodies are involved in many cases, where atrophy of these structures have high specificity. The dorsomedial thalamus is associated with the reported impairment in memory and can be identified antemortem on MRI.3 There is no quantifiable evidence of how much thiamine should be used to prevent WKS. However, thiamine should be given before the administration of glucose whenever WKS is considered.
Our patient. Despite the administration of thiamine (100 mg parenterally for 5 d, followed by oral thiamine 300 mg/d indefinitely), our patient’s memory and cognition remained unchanged. She underwent intensive inpatient rehabilitation for 2 months and was eventually placed in long-term nursing care.
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