Case 4-2001: acute sarcoidosis.

To the Editor: The study by Glaser et al. (Jan. 25 issue)1 identified risk factors for the development of symptomatic cerebral edema in children with diabetic ketoacidosis. Of the 61 children in whom symptomatic cerebral edema developed, 57 percent recovered completely, 21 percent had permanent neurologic damage, and 21 percent died. The investigators did not identify the risk factors for death from cerebral herniation or for permanent neurologic damage. It would be clinically relevant to compare the children who died or had permanent neurologic damage with those who did not have symptomatic cerebral edema or who had symptomatic cerebral edema but recovered completely. The authors conclude that the rate of fluid administration and the tonicity of the fluid that was administered, when analyzed separately, were not related to the risk of cerebral edema. However, they did not evaluate whether the use of hypotonic fluid, when administered at a high rate, was a risk factor for cerebral edema. It is possible that both of these factors are necessary to increase the risk of cerebral edema. Finally, the authors identified three children who had cerebral edema before the initiation of therapy. Did these children receive excessive oral rehydration with hypotonic fluid (such as water) at home, before their presentation at the hospital?


Risk Factors for Cerebral Edema in Children with Diabetic Ketoacidosis
To the Editor: The study by Glaser et al. (Jan. 25 issue) 1 identified risk factors for the development of symptomatic cerebral edema in children with diabetic ketoacidosis. Of the 61 children in whom symptomatic cerebral edema developed, 57 percent recovered completely, 21 percent had permanent neurologic damage, and 21 percent died. The investigators did not identify the risk factors for death from cerebral herniation or for permanent neurologic damage. It would be clinically relevant to compare the children who died or had permanent neurologic damage with those who did not have symptomatic cerebral edema or who had symptomatic cerebral edema but recovered completely.
The authors conclude that the rate of fluid administration and the tonicity of the fluid that was administered, when analyzed separately, were not related to the risk of cerebral edema. However, they did not evaluate whether the use of hypotonic fluid, when administered at a high rate, was a risk factor for cerebral edema. It is possible that both of these factors are necessary to increase the risk of cerebral edema. Finally, the authors identified three children who had cerebral edema before the initiation of therapy. Did these children receive excessive oral rehydration with hypotonic fluid (such as water) at home, before their presentation at the hospital? The authors reply: To the Editor: Dr. Gebara raises several issues that merit responses. First, limiting the cerebral-edema group to patients with adverse outcomes would be relevant only if interventions for the treatment of cerebral edema were ineffective. Although there is limited information about therapy for cerebral edema in children with diabetic ketoacidosis, case reports suggest that prompt initiation of hyperosmolar therapy may be beneficial. 1,2 We therefore cannot assume that the children who survived without sequelae had a less severe form of the disease than those who had adverse outcomes.
Second, although there are theoretical reasons why rapid administration of hypotonic fluids might contribute to cerebral edema, neither the rate of fluid administration nor the rate of sodium administration was significantly associated with cerebral edema in the patients we studied. In addition, in a subanalysis that we conducted, an interaction term combining the rates of fluid and sodium administration was not significantly associated with cerebral edema. We recommend that physicians caring for children with di-abetic ketoacidosis administer rehydration therapy to these patients at moderate rates and that isotonic fluids be used for the initial several hours.
Finally, we do not know whether children who had cerebral edema before in-hospital therapy for diabetic ketoacidosis ingested excess hypotonic fluid at home. Most children with severe diabetic ketoacidosis, however, have a history of persistent vomiting and present with gastrointestinal ileus. It is therefore unlikely that they could both ingest and absorb substantial quantities of fluid at the same time.

Case 4-2001: Acute Sarcoidosis
To the Editor: The February 8 Case Record 1 involves a patient with Löfgren's syndrome. In his discussion of the case, Dr. Bates does not sufficiently emphasize the importance of the recognition of periarticular ankle inflammation as a particular presenting sign of acute sarcoidosis. In the Nordic countries and Spain, Löfgren's syndrome is the most common form of the disease and frequently starts with periarticular ankle inflammation. In our series of 186 white patients with Löfgren's syndrome, 35 (19 percent) presented with periarticular ankle inflammation alone and 46 (25 percent) had periarticular ankle inflammation in association with erythema nodosum. 2 Periarticular ankle inflammation is an acute inflammation of the tissues around the ankles without true arthritis. The typical lesions of erythema nodosum may be absent or may appear concomitantly with periarticular ankle inflammation, or a few days later. Arthrocentesis is ineffective, and biopsy of the inflamed skin shows nonspecific panniculitis. The accompanying clinical and radiologic findings and final outcome are so similar to those of classic Löfgren's syndrome that this condition is considered to be a variant of Löfgren's syndrome, even in the absence of erythema nodosum. 3 The diagnosis of sarcoidosis should be strongly considered in patients who present with periarticular ankle inflammation, whether or not they have associated erythema nodosum, and a chest radiograph should be obtained to confirm the presence of bilateral hilar lymphadenopathy.  To the Editor: Dr. Bates appropriately cites Willan as providing the first description of erythema nodosum in the medical literature, in 1798. However, Leopold Mozart, Wolfgang's father, should receive some credit for his earlier and apt description of that syndrome. In a letter to his wife dated October 30, 1762, Leopold describes his ailing son in the following manner: As he was going to bed, he complained a good deal of his backside and his hips. When he got into bed, I examined the places where he said he had pain and found a few spots as large as a kreutzer [a small Austrian coin], very red and slightly raised and painful to the touch. But they were only on his shins, on both elbows, and a few on his posterior; altogether there were very few. 1 Leopold's description of the evolution of these lesions provides convincing evidence that he should share credit for documenting this important clinical syndrome.

University of Minnesota Medical School
Minneapolis, MN 55455