Methimazole Associated Neutropenia in a Preterm Neonate Treated for Hyperthyroidism

Table 1

Free T4, total T3, and TSH levels as well as white blood cell count and absolute neutrophil counts during hospitalization at our institution. Normal values for FT4: 0.75–1.54 (ng/dL), T3: 0.9–2.6 (ng/mL), and TSH: 0.5–6.5 mIU/L.

Day of life	Free T4	Total T3	TSH	WBCs	ANCs
	(ng/dL)	(ng/mL)	(mIU/L)	(Cells/μL)	(Cells/μL)
10	5.2	2.36	0.02	14000	6160
12	2.16	1.15	0.01
15	1.3	0.98	0.02	16700	3507
17	2.26	2.39	0.03
20	4.99	2.45	0.02
21	3.5	1.48	0.02
23	2.1	0.8	0.02	18200	2002
25	0.7	0.79	0.02
28	0.62	1.23	0.02
30	0.57	1.21	0.04	16005	990
31				15200	870
32				17900	860
33				15900	795
34	0.75	1.19	0.05	13000	870
35				15000	860
36				20000	795
37	0.75	1.62	0.24	15700	942
38				15900	900
39				16500	990
40	1.01	1.32	0.31	19400	2134
41				17100	855
42				16800	1512
43				12800	896
44	0.66	1.13	0.42	14400	2440
45				12100	1444
47	0.54	1.12	1.23	16300	1793