Effect of Erythromycin Estolate After Unsuccessful Malaria‐penicillin Therapy for General Paresis

Abstract

In 1960 we reported our results with combined malaria and massive penicillin therapy of general paresis in elderly patients (1). After this form of treatment, the results of serologic tests for syphilis remained positive in 16 of 20 subjects. Erythromycin estolate then was used to determine whether this additional therapy might cause the test findings to change from positive to negative. METHODSThe 16 paretic patients with continuing positive blood reactions for syphilis following treatment with malaria and massive doses of penicillin were given 250-nig. capsules of erythromycin estolate' orally four times a day for forty days (40 Gm. total). A serologic test (2) for syphilis (V.D.R.L.) was performed before, and at one, four, and six to eight Inonths after starting therapy.Each patient was observed closely for any signs of toxicity or allergy while receiving the medication. RESULTSThere was no alteration in the serology reactions of the 16 patients that could be attributed to the erythromycin therapy ( Table 1).Two patients did not complete the study. One died of cerebral thrombosis during treatment, and in the other case spinal fluid could not be collected because of repeated "bloody taps." Spinal fluid Wassermann reactions did not change ( Table 2).Two patients had diarrhea for a few days at the start of therapy, but this was not severe enough to warrant discontinuing the medication. Allergy or jaundice wa8 not observed. Clinical example:A colored male (Wm. B.) was admitted in 1936 at the age of 41 with a diagnosis of central nervous system syphilis. Spinal fluid and serologic Wassermann reactions were 4-plus.He received a course of malaria therapy with no change in the test results. When penicillin became available nine years later (in 1945) he was given 10 million units of penicillin.2 Six months later his serologic reaction was still 4-plus, and spinal fluid reaction 1-plus. Nine years later (in 1954) he was given a course of 25-nlillion units. This was repeated in four years, but there was no change in his serologic or spinal fluid reactions.Following the course of erythromycin therapy, the one-month and four-month serologic findings showed no change, but at eight months the findings were negative. The spinal 1 The trade name of Eli Lilly and Company for erythromycin estolate (propionyl erythromycin leuryl sulfate) is Ilosone.