Dermatitis herpetiformis Duhring – evaluation of disease severity and tissue transglutaminase levels in 122 patients on dapsone therapy

Figures & data

Table 1. Characteristics of patients. 122 patients (= 100%) suffering from DH included in the study, 118 patients (96.7%) on dapsone therapy, 4 patients (3.2%) only on gluten-free diet, 92 men, 30 women, average age 56 years, min. 25 years, max. 86 years

Disease severity	No of patients	Average age of included patients (years)	Average age of diagnosis (years)
Mild form	69 (56.6%) (49 men, 20 women)	Men 55.2 Women 57.2	33.5
Moderate form	48 (39.3%) (39 men, 9 women)	Men 54.9 Women 56.3	34.1
Severe form	5 (4.1%) (4 men, 1 women)	Men 54.9 Women 56.3	29.8

Table 2. The relation between the mean IgA tissue transglutaminase antibodies (IgA-TGA) level and the average dapsone dose. Due to the violation of normality, we used statistical analysis Spearman Rank Correlation Coefficient (= 0.1330*), which means a very weak degree of relation.

	Age	Dapsone dose	Level IgA-TGA
Pearson correlation	0.0573	1.0000	0.2485
Spearman Correlation	0.0442	1.0000	0.1330*
Pearson P-value	0.5307		0.0366
Spearman P-value	0.5307		0.0366
Count	122	122	71

Graph to Table 2

The relation between the mean IgA tissue transglutaminase antibodies (IgA-TGA) level (axis y) and the average dapsone dose (mg), (axis x).

Table 3. The number of patients according to the level IgA-TGA (in categories 0–10, 10–50, 50–100, more than 100 U/ml, the number of patients 122 = 100%) and according to the dapsone dose (the categories 25, 25–50, 50, 50–100, 100 mg), (Fisher’s exact test).

	The tissue transglutaminase antibodies level - IgA-TGA (U/ml) – No. of patients
	0 to 10 U/ml	10 to 50 U/ml	50 to 100 U/ml	Over 100 U/ml	Total patients (%)
Dose of Dapsone – No. of patients
25 mg	11 (9.0%)	4(3.3%)	0(0%)	0(0%)	15(12.3%)
25–50 mg	10 (8.2%)	2(1.6%)	0(0%)	1(0.9%)	13(10.7%)
50 mg	27(22.1%)	8(6.6%)	2(1.6%)	2(1.6%)	39(31.9%)
50–100 mg	11(9.1%)	4(3.3%)	0(0%)	2(1.6%)	17(13.9%)
100 mg	16(13.1%)	0(0%)	3(2.5%)	3(2.5%)	22(18.0%)
Total patients	75 (61.5%	18 (14.8%)	5 (4.1%)	8 (6.6%)	106 (86.9%)
p-value	p-value = 0.223
Complement to Table 3 The relative frequency according to the dapsone dose. The number of patients (relative frequency in %) according to the IgA-TGA (in categories 0–10, 10–50, 50–100, more than 100 U/ml) and according to the dapsone dose (the categories 25, 25–50, 50, 50–100, 100 mg, the number of patients in the category = 100%).

	The tissue transglutaminase antibodies level - IgA-TGA (U/ml)
Dose of dapsone	0 to 10 U/ml	10 to 50 U/ml	50 to 100 U/ml	Over 100 U/ml	Total patients %
25 mg	11(73.3%)	4(26.7%)	0.0%	0.0%	15 = 100.0%
25–50 mg	10(76.9%)	2(15.4%)	0.0%	1(7.7%)	13 = 100.0%
50 mg	27(69.2%)	8(20.5%)	2(5.1%)	2(5.1%)	39 = 100.0%
50–100 mg	11(64.7%)	4(23.5%)	(0.0%)	2(11.8%)	17 = 100.0%
100 mg	16(72.7%)	0.0%	3(13.6%)	3(13.6%)	22 = 100.0%
p-value = 0.223
Complement to Table 3 – the relative frequency according to the level IgA-TGA The number of patients (relative frequency in %) according to the IgA-TGA (in categories 0–10, 10–50, 50–100, more than 100 U/ml, the number of patients in the category = 100%) and according to the dapsone dose (the categories 25, 25–50, 50, 50–100, 100 mg).

	The tissue transglutaminase antibodies level – IgA-TGA (U/ml)
Dose of dapsone	0 to 10 U/ml	10 to 50 U/ml	50 to 100 U/ml	over 100 U/ml
Total patients	75 = 100%	18 = 100%	5 = 100%	8 = 100%
25 mg	11 (14.7%)	4(38.9%)	0.0%	0.0%
25–50 mg	10(13.3%)	2(11.1%)	0.0%	1(12.5%)
50 mg	27(36.0%)	8 (44.4%)	2 (40.0%)	2(25.0%)
50–100 mg	11(14.6%)	4(38.9%)	(0.0%)	2(25.0%)
100 mg	16 (21.3%)	0.0%	3 (60.0%)	3(37.5%)
p-value	p-value = 0.223

Table 4. Dapsone dose (the average daily dose during the last 3 years in the categories of doses of dapsone 25, 25–50, 50, 50–100, 100 mg) and number of patients with mild, moderate, severe form of DH, 122 patients included in the study = 100%. The relation was confirmed, Fisheŕs exact test.

	Dapsone dose (mg)
	25 mg	25–50 mg	50 mg	50–100 mg	100 mg	total patients%
No. of patients mild form	17 (13.9%)	7 (5.7%)	26 (21.3%)	7 (5.7%)	9 (7.4%)	66 (54.1%)
No. of patients moderate form	0 (0%)	7(5.7%)	16 (13.1%)	12 (9.8%)	12 (9.8%)	47 (38.2%)
No. of patients severe form	0 (0%)	0 (0%)	2 (1.6%)	1 (0.8%)	2 (1.6%)	5 (4.1%)
Total no. of patients	17(13.9%)	14 (11.5%)	44 (36.1%)	20 (16.4%)	23 (18.9%)	118 (96.7%)
p-value	p-value = 0.000619
Complement to Table 4. – the relative frequency according to the severity of disease The number of patients (relative frequency in %) according to the severity of disease (mild, moderate and severe form and to the dapsone dose (the categories 25, 25–50, 50, 50–100, 100 mg)
	Dapsone dose (mg)
	25 mg	25–50 mg	50 mg	50–100 mg	100 mg	Total patients %
No. of patients mild form	17 (25.8%)	7 (10.6%)	26 (39.4%)	7 (10.6%)	9 (13.6%)	66 = 100.0%
No. of patients moderate form	0.0%	7 (14.9%)	16 (34.0%)	12 (25.5%)	12 (25.5%)	47 = 100.0%
No. of patients severe form	0.0%	0.0%	2 (40.0%)	1 (20.0%)	2 (40.0%)	5 = 100.0%
p-value	p-value = 0.000619
Complement to Table 4 – the relative frequency according to the dapsone dose. The number of patients (relative frequency in %) according to the severity of disease (mild, moderate and severe form), and to the dapsone dose (the categories 25, 25–50, 50, 50–100, 100 mg).
	Dapsone dose (mg)
	25 mg	25–50 mg	50 mg	50–100 mg	100 mg	Total patients%
Total number of patients	17 = 100%	14 = 100%	44 = 100%	20 = 100%	23 = 100%	118 = 100%
No. of patients mild form	17 (100%)	7 (50%)	26 (59.1%)	7 (35%)	9 (39.1%)	66 (55.9%)
No. of patients moderate form	0	7 (50%)	16 (36.4%)	12 (60%)	12 (52.2%)	47 (39.8%)
No. of patients severe form	0	0	2 (4.5%)	1 (4.5%)	2 (8.7%)	5 (4.2%)
p - value	p-value = 0.000619

Table 5. The comparison of levels IgA - TGA according to the severity of DH (mild, moderate, severe form), test Kruskal–Wallis One-Way ANOVA. The relation was not confirmed, p-value = 0.166.

N	Form	Median of average TGA (U/ml)	1st quartile	3rd quartile	Kruskal–Wallis One-Way ANOVA
69	Mild	6.25	1.8	44.94	0.166
48	Moderate	14.45	4.3	102.06
5	Severe	10.33	0.75	169.37

The median of average IgA-TGA in mild form is 6.25 U/ml, in moderate form 14.45 U/ml and in severe form 10.33 U/ml. We show the 1st quartile and 3rd quartile, p- value = 0.166.

The graph to Table 5. This graph (Box plot) shows the relation between the severity of DH and the IgA-TGA level.

Table 6. The evaluation of the relation between dose of dapsone and age of patients was calculated, the relation is not confirmed, Spearman test is 0.044* Table 6, Graph 6(a). The evaluation of the relation between the IgA-TGA and the age of patients was calculated, the relation is not confirmed, Spearman test is 0.022**Table 6, Graph 6(b).

	Age	Dapsone dose	Level IgA-TGA
Pearson Correlation	1.0000	0.0573	0.1094
Spearman Correlation	1.0000	0.0442*	0.0221**
Pearson P-value		0.5307	0.3637
Spearman P-value		0.5307	0.3637
Count		122	71

Graph 6 a). The relation dapsone dose (Disulone dose ) and age. The relation is not confirmed. Spearman test is 0.044.

Graph 6 b). The level IgA-TGA and age. The relation is not confirmed. Spearman test is 0.022.