Scurvy is primarily diagnosed based on clinical symptoms and physical examination findings. In cases where the findings suggest scurvy, observed clinical improvement with vitamin C supplementation is strong evidence supporting the diagnosis. Laboratory tests can assist in diagnosis but may not always provide definitive results. While measuring vitamin C levels in blood plasma is a valuable indicator, it may not fully reflect the actual amount of vitamin C in tissues, as it can be influenced by recent dietary intake. Fasting plasma vitamin C levels of 0.6 mg/dl and above typically rule out deficiency, whereas values below 0.2 mg/dl indicate a significant deficiency. Values within this range may lead to diagnostic uncertainty. Measuring intracellular vitamin C levels in leukocytes is considered a more reliable diagnostic method because it is less affected by dietary changes and more accurately reflects tissue levels.