A 15-year-old boy with anemia and leg bruising
Bibliographic record
Abstract
A previously healthy 13-year-old male was brought to the emergency department after fainting. He was uninjured from fainting, but on exam he had a swollen and bruised right calf and petechiae on his left leg. He felt the injuries were from playing soccer the week before. Investigations revealed hemoglobin of 65 g/L. He was admitted and received a blood transfusion bringing his hemoglobin to 100 g/L. Workup for fracture, deep vein thrombosis, systemic vasculitis and coagulopathy were all negative. His skin biopsy showed nonspecific perivascular hemorrhage. The provisional discharge diagnosis was atypical Henoch-Schönlein purpura. One week later, the patient fainted again and returned to the hospital. His left calf was more swollen, with bruising from the knee to ankle. There were corkscrew hairs on his left thigh. He had no other signs of blood loss but his hemoglobin had fallen to 61 g/L. Further workup for arteriovenous malformation, infections, plasminogen activator inhibitor deficiency, α-2-antiplasmin deficiency, von Willebrand’s disease, Quebec platelet disorder and factor deficiency were negative. T2-enhanced magnetic resonance imaging of the right leg demonstrated increased signal intensities in the bone of the distal femur, proximal tibia and fibula. A thorough review of the patient’s history finally clarified the diagnosis. Detailed review of the patient’s dietary history revealed an extremely restricted diet. His diet essentially consisted of hot dogs, pizza and boxed macaroni and cheese, with no intake of fruit or vegetables. None of the foods in his diet were a significant source of vitamin C. Classic physical features of vitamin C deficiency include petechiae, ecchymoses, hyperkeratosis, corkscrew hairs, gingival hyperplasia and easy gingival bleeding. The rapid decline in his hemoglobin level at the second admission was likely from loss in his lower leg that had significant bruising and swelling. Clinically, he met the diagnostic criteria for scurvy and was started on oral vitamin C (L-ascorbic acid) therapy. Within 2 days his energy started to improve. The result of his vitamin C level was available 1 week later, confirming the diagnosis; his serum vitamin C level was <5 µmol/L (normal >28 µmol/L). Vitamin C is critical for collagen synthesis, dentine and bone formation and intercellular connective tissue stability. Abnormal or decreased collagen production from vitamin C deficiency can result in a myriad of symptoms. Our patient had low energy, microcytic anemia, low iron stores, depressed mood, corkscrew hairs, increased T2 signal intensities of the lower leg bones on magnetic resonance imaging, perifollicular hemorrhages, normal appearing gingiva and spontaneous hematoma. These findings are all in keeping with vitamin C deficiency (1). Scurvy, the medical condition caused by vitamin C deficiency, is one of the oldest diseases in human history. Now considered rare, it is still occasionally seen in children with developmental disabilities and restricted diets. Deficiency can develop as quickly as 1 to 3 months after insufficient intake. There are no data in children, but a recent Canadian study of university students found 33% age 20 to 29 had suboptimal levels of vitamin C (11 to 28 µmol/L) and 14% were deficient (<11 µmol/L) of vitamin C (2). Measurement of serum vitamin C level can be inaccurate. Often clinical diagnosis with dietary history, physical examination and resolution with treatment is sufficient to confirm diagnosis. A low plasma vitamin C level is diagnostic; however, a normal value can be misleading because it reflects recent, not long-term ingestion. A more sensitive test involves measuring the vitamin C level in the buffy-coat of white blood cells. This test is not widely available and can be technically challenging to complete. Measuring urinary excretion of vitamin C after parenteral administration is another method to evaluate body stores. One hundred milligrams of vitamin C are given intravenously. If less than 80% of the dose is excreted 5 hours later, this indicates increased vitamin C retention and insufficient body stores. Treatment of scurvy is simple. Supplementation with 100 to 300 mg a day in children and 500 to 1000 mg per day in adults of oral vitamin C for 4 weeks and correction of diet allows for complete recovery. Ecchymosis and bony changes may take several weeks to months to resolve. Our patient’s energy and mood improved and his hemoglobin stabilized within the first couple days. His leg was entirely healed about 1 month after treatment started. Symptoms of vitamin C deficiency mimic rheumatologic, hematologic and infectious illnesses. Physicians caring for children should be aware that scurvy still exists and they should refamiliarize themselves with common presenting symptoms. University students often have inadequate diets and demonstrate deficient levels of vitamin C. There is reason to believe the same may be true in younger children with picky eating habits. Thoroughly gathering dietary history details, especially in this case would have resulted in prompt and correct diagnosis and treatment sooner while eliminating the extensive workup. Vitamin C deficiency can present with nonspecific symptoms and should be considered, particularly in cases of unexplained anemia, petechiae and musculoskeletal pain. Children who are ‘picky eaters’ and have restricted diets may be at risk of vitamin C deficiency. Taking a thorough dietary history is essential with all patient encounters.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.010 |
| Meta-epidemiology (narrow) | 0.003 | 0.001 |
| Meta-epidemiology (broad) | 0.003 | 0.002 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.002 | 0.003 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.014 | 0.012 |
| Insufficient payload (model declined to judge) | 0.003 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".