The coagulopathy induced by vitamin K deficiency commonly results from our lack of awareness of the clinical setting associated with vitamin K deficiency. Thirteen cases are reviewed to illustrate the clinical correlates most frequently observed. Dietary deficiency was always present, but concomitant antibiotic therapy was not an absolute requirement. The postoperative patient is at high risk, as is the patient with cancer or renal failure. Abnormal bleeding was common, but significant hemorrhage occurred only in postoperative patients. Factor assays were helpful and occasionally necessary to make the diagnosis, but a therapeutic trial with parenteral vitamin K was often enough to provide the right diagnosis. Greater awareness of this deficiency syndrome is necessary to avoid the serious morbidity that often results.
(JAMA 238:40-42, 1977)