Among the unavoidable changes which take place in milk when it is heated, and which have been considered as etiological factors in in fantile scurvy are: (1) the destruction of a certain amount of nucleon phosphorus; (2) the destruction of all enzymes; (3) the change of soluble calcium compounds into insoluble calcium phosphate; (4) the conversion of a certain amount of the amorphous neutral calcium citrate into the less soluble crystalline form. Netter considers citric acid as the specific antiscorbutic constituent of cow's milk, but as the latter is much richer in citric acid than is mother's milk, a deficit cannot easily occur even with cooking.
Johannessen, in conformity with the recent theory that marine scurvy is due to an intoxication, suggests that toxins from the killed bacteria in the milk may have a part in the production of infantile scurvy. Neumann seeks the cause in a chronic poisoning: "The poison may arise exogenously from the food by bacterial action, by chemical means or by the action of heat, or it may arise endogenously during diges tion." In the conclusions which are drawn from the collective studies of the question by the American Pediatric Society the possibility of an autointoxication is suggested. The supposition that infantile scurvy is due to some toxin arising in the food and that this affects only certain susceptible children while the great majority thrive on the same nour ishment would most easily explain the whole symptom-complex, and the prompt action of dietetic therapy, the result of a simple change in diet.
Microscopic examination of the blood and other tissues, and special bacteriological experiments (Schniorl) have so far given no support to the theory of a direct bacterial origin of the disease, nor have any results been derived from its attempted artificial production in animals (Bar tenstei n).
one carefully considers the symptoms which have already been described, this disease will hardly be mistaken for any other, but it is of great importance to make the diagnosis before the disease gains much headway. If in a bottle-fed infant a progressively severe anemia develops with a coexistent. suspicion of hemorrhagic swelling of the gums, and tenderness at the epiphyseal ends of the long bones one should think of Barlow's disease—infantile scurvy.
Mistakes frequently occur through the observation of marked uni lateral swellings on the long bones; the diagnosis of periostitis, ostitis, osteomyelitis, osteosarcoma, etc., is made, even operations of greater or less magnitude are undertaken without result, until the death of the child or the discovery of subperiosteal hemorrhages puts one on the right track. The entire clinical picture should not be neglected, the severe amemia, and its gradual development should be sufficiently appreciated; the entire child should be examined.
In contrast to severe anemnias from other causes with a tendency to the occurrence of hemorrhages, it is important to remember that aside from a considerable reduction in the percentage of the blood changes in infantile scurvy are not characteristic (see above). Infantile scurvy is readily hidden behind an associated rachitis, or may be mistaken for rachitis, though the latter does not exist at the time. For this reason the progressive anemia, the affection of the gums, and the painful swellings on the long bones are all very impor taut. Swelling and sensitiveness at the osteocartilaginous border of the ribs is common to both diseases; an angular fracture between the prominent bony part and the depressed cartilage, or possibly even a depression of the sternum together with the cartilaginous portion of the ribs speaks for infantile scurvy. In congenital syphilis swellings similar to those of infantile scurvy appear on the long bones, and the condition of pseudoparalysis is frequent in congenital syphilis, marked anemia also occurs, but in addition there are the other usual symptoms of syph ilis. The peculiar gingivitis and eventually the other signs of the hremor rhagic diathesis are very valuable. Radiographs of the diseased bones can be of especial service in difficult cases.
Incipient and abortive examples of infantile scurvy make them selves evident by the increasing anemia, the restlessness and the hyper iesthesia of the children.
Prognosis.—In simple cases the prognosis is favorable if the diag nosis is made and dietetic therapy instituted; but if a complicating intestinal catarrh or bronchopneumonia exists, or if the cardiac strength of the child has already seriously suffered, the prognosis is doubtful in spite of proper feeding.