7. Secondary malnutrition

Examination of the capacity for catch-up in affluent children, with stunting secondary to disease, has the advantage that these groups are less likely to have had early developmental problems and malnourished parents. On the other hand, even with treatment, their residual disease, previous surgery, special diets and drugs may each restrict their recovery. There are many case reports of impressive catch-up (Prader, Tanner & Harnack, 1963; Prader, 1978; Tanner, 1981). For example, two hypopituitary dwarfs were treated with growth hormone and androgen when aged 23 and 24 years; they subsequently gained 22 and 21 cm (Van der Werff Ten Bosch & Bot, 1986). Another patient, who had constrictive pericarditis, corrected surgically at the age of 18, subsequently gained 32 cm (Van den Brande, 1986). The patients each had delayed bone maturity. These reports serve to illustrate that catch-up is possible even at a chronological age when growth has normally ceased; where catch-up is not observed it does not mean that it is not possible-only that we have not yet found the correct way of bringing it about.

Most children with stunting secondary to renal or intestinal disease fail to catch up to their expected adult height.

7.1. Renal disease

In patients either treated conservatively or by renal transplantation, subsequent growth has been varied and disappointing (Guest & Broyer, 1991; Ingelfinger et al., 1981; Polito et al., 1987; Van Diemen Steenvoorde et al., 1987; So et al., 1987; Fennell et al., 1986; Ellis et al., 1985; Rizzoni, Basso & Setari, 1984). In general, one third of the children have a reasonable acceleration of height, particularly if they are less than 7 years of age (Ingelfinger et al., 1981). The failure to catch-up is mainly due to treatment with steroids. Those that have other types of immuno-suppression seem to have much better compensatory growth (Knight, Roy & Sheil, 1985), although there are reports of exceptional growth when steroids are given intermittently (Steendijk, 1986).

7.2. Intestinal disease

Prader's group (Barr, Shmerling & Prader, 1972) studied compensatory growth in coeliac patients, aged 9-15 months. These patients' height and bone age were similarly retarded. Complete catch-up was observed. The children were normal in height and bone age within two years of the start of treatment. Children over 3 years of age, when diagnosed, although severely stunted, usually have heights that are in keeping with their bone ages, and so complete catch-up growth should be achievable (Exner et al., 1978); however, in other centres about half these children fail to have a significant catch-up (Fagundes-Neto, Stump & Wehba, 1981).

Older children (11 to 17 years) with Crohn's disease show a marked height 'spurt' after surgery (Lipson et al., 1990). Follow-up of groups of short children with Crohn's disease into adult life shows that most attain normal adult height (Castile, Telander & Cooney, 1980; Markokwitz et al., 1993); about one third remain stunted. Permanent growth failure was much less common in subjects with stunting due to ulcerative colitis (10%) (Markowitz et al., 1993; Kirschner, Voinchet & Bosenberg, 1978).

Unlike inflammatory bowel disease, complete clinical reversibility, without need for continued treatment, characterises stunted children with trichuris dysentery syndrome. Cooper et al. (1990) gave such children anthelminthic treatment without any other change in their circumstances. The children had an enormous height spurt. This study is important because it shows that children living in poor conditions in countries where stunting is common can, even in later childhood, have very substantial catch-up in height.