Table 3.
Observational or uncontrolled lactose-related studies in children with AP-FGIDs
| Authors [Ref.], country (year) | Methods | Findings |
|---|---|---|
| Liebman et al. [47], USA, (1979) | RAP (n = 38) versus controls (n = 29) completed lactose dietary challenges 17 RAP (n = 11 malabsorbers and n = 6 absorbers) underwent lactose-free diet |
11/38 RAP versus 1/29 controls with positive lactose challenge (malabsorbers) (p < 0.01) 10/11 malabsorbers versus 0/6 absorbers had total relief of symptoms on diet (p < 0.001) |
| Barr et al. [8], USA (1979) | RAP (n = 80) completed LHBT 28 with positive LHBT placed on 6-week non-blinded dietary trial (2 weeks lactose free, 2 weeks lactose, 2 weeks lactose free) |
32/80 (40%) LHBT positive 20/28 (71%) exacerbation of pain on lactose versus lactose-free diet (p < 0.01) |
| Christensen [41], Denmark (1986) | RAP (n = 50) versus controls (n = 40) completed lactose tolerance testing (2 g/kg); determined positive if abdominal pain and/or diarrhea developed | 1/50 RAP children found to be lactose intolerant versus 0/40 controls (p = 1.0) |
| Lebenthal et al. [20], USA (1981) | RAP (n = 69 underwent LHBT) 12-month milk elimination diet in positive LHBT (n = 15) versus negative LHBT (n = 13) |
21/69 RAP LHBT positive 6/15 positive LHBT versus 5/13 negative LHBT had elimination of pain (p = 0.93) |
| Blumenthal et al. [48], UK (1981) | RAP (n = 26) given LHBT (2 g/kg up to 50g, 20% solution) | 3/26 (12%) LHBT positive 1 of 2 children with positive LHBT improved on lactose-free diet |
| Wald et al. [49], USA (1982) | RAP (n = 40) completed LHBT (2 g/kg, up to 50 g) Dietary intervention (total 6 weeks): 2 weeks lactose elimination, 2 weeks lactose-containing, 2 weeks lactose elimination |
12/40 (30%) LHBT positive at 2 g/kg 3/12 (25%) positive LHBT versus 5/28 (18%) negative LHBT (p = 0.68) with significant improvement on lactose-free diet |
| Bhan et al. [50], India (1982) | RAP (n = 70) versus controls (n = 50) lactose tolerance testing All RAP children started on 4-week lactose-free diet |
33/70 RAP (47%) versus 9/50 (18%) controls were lactose malabsorbers (p < 0.01) 11/33 (33%) lactose malabsorbers improved versus 6/37 (16%) lactose absorbers on diet (p < 0.01) |
| Webster et al. [51], USA (1995) | RAP (n = 137) given LHBT (1 g/kg, 10% solution) Those with positive LHBT recommended to have lactose elimination diets; telephone follow-up in 115/137 (84%) |
LHBT positive in 33/137 (24%) In follow-up, 20/27 (74%) of lactose malabsorbers had less frequent abdominal pain versus 28/88 (32%) lactose absorbers (p < 0.001) |
| Ceriani et al. [52], Italy (1988) | RAP (n = 32) given LHBT (2 g/kg up to 50 g) 18 LHBT positive placed on lactose-free diet |
24/32 (75%) LHBT positive 14/18 (78%) LHBT positive improved on the diet |
| Gremse et al. [53], USA (1999) | RAP (n = 146) given LHBT (1 g/kg, 10% solution) | LHBT positive in 50/146 (34%) |
| Boey [54], Malaysia (2001) | RAP (n = 24) given LHBT (2 g/kg) All participants started on lactose-free diet |
17/24 (71%) LHBT positive None responded to lactose-free diet |
| Gijsbers et al. [55], The Netherlands (2012) | RAP (n = 220) given LHBT (2 g/kg) In those with positive LHBT: initial lactose elimination, provocation with lactose if symptoms resolved, followed by double-blind placebo controlled challenge undertaken for ‘definite proof’ of causal relationship |
57/210 (27%) LHBT positive 24/38 (63%) with positive LHBT improved on lactose elimination diet 7/23 (30%) of those who improved had worsening symptoms with provocation None of the 6 subsequently investigated via double-blind challenge had specific lactose-related symptoms |
| Ockeloen et al. [56], The Netherlands (2012) | Retrospective review of LHBT testing in children with chronic abdominal pain (n = 91); subsequent follow-up following lactose-free diet in those with positive LHBT | 22/91 (24%) LHBT positive 21/22 (95%) improved on lactose free-diet at 5 months, and 14/22 (64%) continued with improvement at 15 months’ follow-up |
| Dabritz et al. [27], Germany (2014) | AP-FGID children, of whom 161 completed LHBT | 35/161 (22%) LHBT positive Unclear how many specifically improved on a lactose free-diet |
LHBT = Lactose hydrogen breath test.