Table 1

Presence of anti-microsomal protein antibodies in sera of patients with a clinical history consistent with delayed-onset sulfonamide hypersensitivity reactions

Patient	Negative	55 kDa	80 kDa	96 kDa	Sulfonamide exposure	Time to sample collection^1-a
Group IIA
1		++			SMX-TMP^1-b	5 mo
3	+				SMX-TMP	5 yr
13^1-e		+	+		SMX-TMP	4 weeks
14	+				SMX-TMP	>1 yr
15		+	+		SMX-TMP	1 yr
16		++	+		SMX-TMP	4 mo
17		+			SSX-ERY^1-c	1 mo
18		+			SMX-TMP	1 yr
19		+++			“Sulfa”^1-d	11 mo
45^1-f		++		++	SMX-TMP	4 mo
46^1-g				++	SMX-TMP	3 mo
50		+			SMX-TMP	1 yr
51		++			SMX-TMP	1 yr
52	+				SMX-TMP	4 yr
53^1-h		+++			SMX-TMP	7 weeks
Group IIB
5		++			“Sulfa”	Not known
7		+++			SMX-TMP	3 mo
24			+		“Sulfa”	3 yr
27	+				“Sulfa”	Not known
36				+	Trisulfaminic	3 weeks
48		++			“Sulfa”	2 mo

↵1-a Time from clinical adverse event and discontinuation of sulfonamide administration to collection of sample.
↵1-b Sulfamethoxazole-trimethoprim.
↵1-c Sulfisoxazole acetyl/erythromycin.
↵1-d Unspecified sulfonamide antimicrobial.
↵1-e Also had antibodies recognizing all SMX-modified proteins, including the 45- to 55-kDa, 96-kDa, 100-kDa and 150-kDa proteins, as a result of recognition of the SMX hapten; see text for details.
↵1-f Also had antibodies against a 54-kDa protein.
↵1-g Also had antibodies against a 30-kDa protein.
↵1-h Also had anti-thyroid peroxidase antibodies.