Asosiasi dan Disosiasi Insulin-Antibodi Insulin pada pasien Sindrom Autoimun Insulin.

Abstract

Abstrak

Sindrom autoimun insulin (SAI) ditandai oleh pembentukan autoantibodi pada pasien yang sebelumnya tidak
pernah menggunakan insulin. Pasien SAI biasanya mengalami hiperglikemia diikuti dengan hipoglikemia
sesudah makan, yang terjadi karena asosiasi dan disosiasi insulin dari kompleks antibodi insulin-insulin. Studi ini
dilakukan untuk mengevaluasi perubahan konsentrasi insulin imunoreaktif bebas (IIB), insulin imunoreaktif total
(IIT), antibodi anti insulin dan gula darah pada saat uji toleransi glukosa oral 75 g (TTGO). Pada fase pertama,
setelah dimulai uji toleransi, konsentrasi antibodi insulin turun dari 54% ke 45%, selama 120 menit. Hal itu
menunjukkan terjadi ikatan insulin dengan antibodi hingga menyebabkan kenaikan insulin terikat (IIT) pada
waktu bersamaan. Gula darah naik sampai 200 mg% dalam 60 menit karena IIB relatif tidak cukup untuk
menekan kenaikan gula darah sesudah uji toleransi glukosa. Fase kedua, 120 menit sesudah TTGO, konsentrasi
IIT dan antibodi insulin kembali ketingkat basal. Perubahan itu menunjukkan disosiasi insulin dengan kompleks
insulin-antibodi. Gula darah turun menjadi 33 mg% pada waktu 240 menit, mungkin karena ekses IIB yang
dihasilkan kompleks insulin-insulin antibodi. Hal itu menunjukkan bahwa asosiasi insulin terhadap antibodi
menyebabkan hiperglikemia 60 menit setelah TTGO dan disosiasi dari kompleks insulin-insulin antibodi
menyebabkan hipoglikemia 240 menit setelah TTGO.

Kata kunci: antibodi insulin, glukosa darah, asosiasi, disosiasi.

Abstract

The insulin autoimmune syndrome ( IAS ) is characterized by the autoantibodies formation in patient without
previous insulin usage. Patient affected by IAS usually developed hyperglycemia followed by hypoglycemia
after meal due to association of insulin to its antibody and dissociation of insulin from insulin-insulin antibodies
complexes. This study was carried out by evaluation of the changes of the free immunoreactive insulin (FIRI)
concentration and the total immunoreactive insulin (TIRI) concentration. Insulin antibody and blood sugar during
75 g oral glucose tolerance test (75 g OGTT) also evaluated. There were two distinct time courses could be
identified during the OGTT. The insulin antibody concentration gradually decreased from 54% to 45% at 120
minutes. That change indicates consumption of the antibody or association of the insulin to its antibody, results in
the increase of bound insulin or TIRI at the same time. The blood sugar increased to 200 mg% in 60 minutes due
to relativity insufficient of FIRI to supress blood sugar elevation after OGTT. After 120 minutes of OGTT the
concentrations of TIRI and the insulin antibodies were returned to the basal level and these changes were strongly
indicated the dissociation of the insulin–insulin antibodies complexes. Blood sugar was decreased to 33 mg% at
240 minutes, may be due to the relativity excess of FIRI released from insulin-insulin antibodies complexes.
These data indicated that association of the insulin to its antibody result in hyperglycemia 60 minutes after OGTT
and dissociation of the insulin-insulin antibodies complexes result in hypoglycemia 240 minutes after OGTT.

Keywords: insulin antibody, blood glucose, association, dissociation.