GRAND
ROUND
SERIES
Rickets
Robert
D. Lovinger,
MD
From the Departments of Pediatrics and Pathology, Medical College of Virginia, Richmond
Rickets is a disease of growing children.
Histori-cally, its winter prevalence and its occurrence
among children confined to sunless sweat shops and smog-ridden cities during the industri1 revolution implicated insufficient exposure to sunlight in its etiology. ‘- Despite the discovery of the anti-rachi-tic action of cod-liver oil more than 200 years ago, rickets remained a serious health problem until the early part of the 20th century when the identifica-tion, isolation, and finally almost ubiquitous addi-tion of vitamin D to our food supply soon rendered
conventional rickets a disorder of mere academic
interest. Recently, however, a slow increase in the
incidence of rickets in children with a variety of
medical problems including renal tubular disorders, illness requiring chronic hemodialysis, cystic fibro-sis, and as a complication of anticonvulsant therapy
has
been noted. Thus, the reappearance of rickets in new, more subtle forms, necessitates increased physician awareness of its incidence and its patho-genesis.CALCIUM AND PHOSPHORUS HOMEOSTASES
Fundamental to the pathophysiology of rickets
are calcium and phosphorus homeostases.4 Calcium
plays a central role in many body functions and is
an important cofactor in muscle contraction, neural
transmission, enzyme activity, blood clotting, and
other cellular processes. Calcium exists in a number of body pools of varying exchangeability or
availa-biity for immediate use. The nonexchangeable
cal-cium pool includes the bones, which contain
ap-proximately 99% of the body’s calcium, and certain
Received for publication Dec 21, 1979; accepted Feb 11, 1980.
Reprint requests to (R.D.L.) Dept of Pediatrics and Pathology, Medical College of Virginia, P0 Box 6, MCV Station, Richmond,
VA 23298.
PEDIATRICS (ISSN 0031 4005). Copyright © 1980 by the American Academy of Pediatrics.
body proteins to which it is tightly complexed. The rapidly exchangeable pool is made up of either
ionized or loosely complexed calcium, present both
in the body fluids and
within
individual cells. A slowly diffusable pool, found in subcellular organ-elles, is not pertinent to our discussion.In the blood, calcium exists in equilibrium
be-tween diffusable and nondiffusable forms. It may
be tightly bound to plasma proteins and thus
func-tionally unavailable to the body, or it may be either free or complexed to other ions, providing instant availability for participation in metabolic activities,
which in turn control its homeostasis. The
propor-tion of free to bound calcium, influenced in part by the blood pH, is the essential factor in the
mainte-nance of the integrity of calcium dependent
pro-cesses.
Despite variations in the dietary intake of
cal-cium, blood calcium concentration is controlled
within precise limits. It is regulated principally by three hormones: parathyroid hormone, calcitonin,
and 1,25-dihydroxycholecalciferol (active vitamin
D)4’5 as seen in the Figure. Parathyroid hormone (PTH) acts to raise blood calcium levels, its synthe-sis and release being stimulated primarily by a decrease in the level of ionized calcium. Once
Se-creted, PTH is biologically active upon bone,
kid-ney, and possibly intestinal cells. In the kidney, PTH stimulates calcium reabsorption while
en-hancing net phosphate excretion. It modulates the
activity of the renal enzyme 25-hydroxy vitamin D
la-hydroxylase. In the intestine it may influence
calcium absorption by increasing cellular transport.
Calcitonin produced by neural-crest-derived
para-follicular or “C” cells of the parathyroid, thyroid, and thymus opposes the action of PTH by lowering serum calcium levels. It is stimulated by increased
concentrations of ionized calcium and acts in the
Vitamin
0
0
Vit.D
\Co\
protein4 Co.-”}
4
lCoj1pre
I
r protesn/ ECF
PARATHYROID
HORMONE
Figure. Principal hormones involved in the regulation of blood calcium concentration are shown. Parathyroid hormone elevates blood calcium concentration; calcitonin
and in the kidney by increasing calcium excretion and possibly by inhibiting the renal activation of vitamin D and intestinal calcium absorption.
Vi-tamin D is a cholesterol-derived hormone present
in both animals (cholecalciferol) and plants
(ergo-calciferol).
In man, vitamin D is either ingested or synthe-sized from 7-dehydrocholesterol found in the skin: ultraviolet irradiation induces the formation of
cho-lecalciferol (vitamin D3), which is transported to
the liver where it is hydroxylated at the 25 position
to form 25-hydrocholecalciferol (25-OHD3). In
pharmacologic doses 25-OHD3 appears to elevate
serum calcium concentration by enhancing bone
reabsorption and by increasing intestinal calcium
absorption. 25-OHD3 is either stored or transported to the kidney where it is “activated” by
hydroxyl-ation at the carbon-i position to 1,25(OH)2D3 by
VITAMIN
0
________has the opposite effect. Active vitamin D is necessary for calcium absorption from the gut.
the renal enzyme la-hydroxylase, whose concentra-tion is controlled by PTH. Once activated its
pri-mary action is in the intestine where it induces the
formation of a transport protein which enhances
the absorption of dietary calcium and phosphate. Both at the level of the bone and renal tubule it also acts as a cofactor for PTH action and may directly suppress PTH secretion. Another vitamin D metabolite, 24,25(OH)2D3, also formed in the kidney, may have an important role in PTH regu-lation.
Phosphate concentration also plays an important role in the regulation of i,25(OH)2D3 synthesis. Hypophosphatemia stimulates production of active
is an elevation in blood phosphate and a decrease in 1,25(OH)2D3 production.
PATHOGENESIS
Clinically, rickets develops in an otherwise
nor-mal bone matrix when inadequate amounts of
cal-cium and/or phosphorus in the extracellular fluid
upset the critical ratio of calcium to phosphorus
necessary for normal mineralization.6 The bone
ma-trix or osteoid continues to be produced at its usual
rate and its accumulation becomes disproportionate to the amount of calcification. Once the epiphyses
have closed, this process is called osteomalacia.
Type 1 Rickets
Classification. Although rickets has been classi-fled in numerous ways, the scheme of Harrison and
co-workers,6’7 who divide the various forms into two main types according to their pathogenesis, is
pre-ferred: (1) those in which an abnormality of vitamin D metabolism leads to a deficiency of active vitamin D (i,25(OH)2D3); and (2) those attributable to a
target tissue abnormality, specifically the renal
tu-bular disorders characterized by defective renal tu-bular reabsorption of phosphate as ifiustrated in
the Table. In the vitamin D deficient group, because
chemical transformation of vitamin D occurs
se-quentially in a number of sites in the body (skin,
liver, kidney), interference with the process at any
of these sites will decrease or inhibit the formation
TABLE. Classification of Rickets
of the final product. Inadequate exposure to
sun-light, deficient nutritional vitamin D intake, 8,9
mal-absorption of fat-soluble vitamins for any
reason,’#{176}”1 liver disease leading to failure of 25-hydroxylation’2 and/or malabsorption, and renal
glomerular destruction’3’14 resulting in depressed
vitamin D activation are all well known causes of type 1 rickets.
Among the newly emerging rachitic forms, at least two fall into the type i category. Rickets in
patients on anticonvulsant therapy, especially those on combinations of phenobarbital and dilantin, may
be the result of increased hepatic metabolism.’’8
Increased induction of liver microsomal enzyme
concentrations by anticonvulsants is thought to cause inactivation and excretion of active vitamin D and its hepatic derived precursors, thereby
re-ducing both the amount of 25-OHD3 presented to
the kidney and the concentration of previously ac-tivated vitamin D. In these patients clinical and radiographic signs of rickets are rare, the only
evi-dence of the disorder being an elevated alkaline
phosphatase or slightly depressed serum calcium.
In cystic fibrosis, reduced serum 25-hydroxy
vi-tamin D concentrations and disordered mineral
me-tabolism have recently been noted.’9 The
appear-ance of rickets in those patients was thought to be due to malabsorption, even in the absence of clinical symptoms of steatorrhea, despite adequate
pan-creatic enzyme replacement and a vitamin D intake
three times that of control subjects. Mean PTH
Classification Diagnosis Treatment
Clinical Biochemical Radiographic
Type 1:
Abnormality of vi- Enlarged, distorted Parathyroid hor- Widening, cupping, Vitamin D, DHT, or
tamin D metabo- bones mone if fraying, stippling 1,25(OH)2D3 in
ap-lism causing defi- Muscle weakness Alkaline phospha- of cartilage-shaft propriate doses to
ciency of active Chest deformities tase junctions normalize serum
al-vitamin D Kyphoscoliosis Growth failure Tetany
Craniotabes
Delayed fontanelle and suture closing Frontal thickening
and bossing
Aminoaciduna if Serum
calcium
N-Serum
phosphate
Fractures Pelvic deformities
kaline phosphatase, calcium and phos-phate
Monitor healing with
serial radiographs
Type 2:
Renal tubular disor- Same as above ex- Parathyroid hor- Same as above ex- Phosphate in amount ders leading to de- cept skeletal de- mone N-* cept spine and sufficient to main-fective reabsorp- formities of the Alkaline phospha- pelvis usually not tam serum levels tion of phosphate head less marked
Growth retardation may be severe and
precede bony changes
tase
Aminoaciduria N
-Serum calcium N Serum
phosphate
involved Nephrocalcinosis
greater than 4 mgI
100 ml vitamin D,
DHT or 1,25 (OH)2D3 to prevent hypocalcemia
levels were significantly elevated in comparison to
matched controls. Bone density was decreased as
measured by densitometry but this was not
radio-graphically evident. Alkaline phosphatase was not
measured.
Finally among the type i rickets is a disorder caused by a functional reduction in the concentra-tion of kidney la-hydroxylase enzyme, the so-called
vitamin D dependent rickets (pseudovitamin D
de-ficiency, increased requirement for vitamin D). This
heterogeneous syndrome, transmitted as an
auto-somal recessive, is due to incomplete conversion of
25-OHD:3 to i,25(OH)2D3.2#{176}22 A deficiency in the
response of the end organ receptors to active
vi-tamin D has also been reported.23
Clinical Characteristics. The diagnosis of any of the forms of vitamin D deficient rickets is usually
established by clinical, biochemical, and
radio-graphic criteria. Rickets characteristically occurs in
premature infants being breast fed without
supple-mentation; at 2 or more months of age the infant is
brought to the emergency room with tetanic
con-vulsions during an acute infection.2427 In older chil-dren, clinical manifestations of rickets occur only after a long period of vitamin D insufficiency. In these patients osteoid accumulates
disproportion-ately because of poor mineralization. Areas of
thin-ning resulting in a ping-pong ball sensation on pal-pation (craniotabes) appear in the skull, while su-ture and fontanelle closure are delayed and frontal thickening and bossing become evident. Teeth may show defective enamel and increased caries. In
other bones the clinical manifestations result from
osteoid overgrowth that has produced enlarged,
weak, unstable shafts. In wrists and ankles, knobby
widened epiphyses become readily palpable.
Weight-bearing and normal muscle tension cause
twisting, bending, rotation, and eventual distortion
of many bones. A waddling gate secondary to
gro-tesque femoral bowing and tibial torsion is common.
Chest deformities include the “pigeon breast,”
aris-ing from sternal protrusion with use of accessory
breathing muscles, and Harrison’s groove, an area
or
rib indentation at the insertion of the diaphragm. Enlarged costochondral junctions form the visibleprominences known as the rachitic rosary. Further
progression of the vitamin D deficiency state leads to deformities of the vertebral bodies and
kypho-scoliosis. Pelvic growth may be compromised
lead-ing to dystocia during childbearing years.
General-ized muscle weakness may also occur but its mech-anism is not specifically known.#{176} Biochemically, vitamin D deficiency is characterized by hyperpara-thyroidism, secondary to transient hypocalcemia, resulting in bone reabsorption due to destruction of the bone matrix and aminoaciduria secondary to impaired renal tubular reabsorption.31’32 Alkaline
phosphatase levels increase dramatically while
se-rum calcium levels remain in the low-normal range
till late in the course of the disease, at which time they decline. Serum phosphate levels remain low; thus mineralization fails to occur despite normal
calcium concentrations.
Radiographic confirmation of rachitic bone
changes is helpful, except in the newborn period
when it has little diagnostic value but provides a base to assess subsequent healing. Although no single radiographic change is distinctive, a
combi-nation of signs, including cupping, spreading, fray-ing, stippling, and widening of the cartilage shaft junction and the presence of uncalcified bone
be-tween the calcified metaphyses and epiphyses, is
characteristic. The most useful areas for radiologic confirmation are the distal radius and ulna.
Type 2 Rickets
The second type of rickets, the target cell abnor-mality group, accompanies a number of renal tu-bular disorders in which there is decreased
reab-sorption of phosphate, thereby lowering the
extra-cellular fluid phosphate concentration.32m The common denominator in this group is “leaky kid-neys,” and the failure of bone mineralization is a
consequence of inadequate serum phosphate levels,
rather than calcium. Secondary
hyperparathy-roidism does not
usually
occur in this group. Thethree most common disorders of this type are: (1) primary renal hypophosphatemic rickets (familial vitamin D resistant rickets and osteomalacia); (2) renal tubular acidosis; and (3) Fanconi syndrome. Renal hypophosphatemic rickets is a familial
dis-order usually transmitted as an X-linked dominant
trait, thus rendering the hemizygous-X males the
more severely affected.’36 In this disease not only
is renal tubular phosphorus resorption affected but absorption from the gut also appears to be
dimin-ished.37 It is manifested early in life by
hypophos-phatemia and growth failure. Skeletal deformities
of the head are less marked than in the type i
rickets; it is the bony deformities of the lower extremities that are characteristic. Biochemically,
the serum alkaline phosphatase is elevated but
there is no aminoaciduria. The radiographic
changes are those of rickets, but the spine and
pelvis are not involved.
Renal tubular acidosis and Fanconi syndrome encompass a group of complex tubular abnormali-ties affecting not only phosphate reabsorption but
other tubular functions as well. In renal tubular
evi-dence of nephrocalcinosis may appear before rach-itic changes are seen. In Fanconi syndrome, one classically sees the triad of hypophosphatemia,
gen-eralized aminoaciduria and renal glucosuria. Other kidney functions, including resorption of water,
bi-carbonate, and potassium, may also be affected. Its
clinical presentation is similar to that of renal
tu-bular acidosis.
TREATMENT
Vitamin D deficiency rickets can be prevented by
the ingestion of the minimum daily requirement of
400
units of vitamin D each day. For infants this is provided by one quart of fortified cow’s milk or anequivalent amount of prepared infant formula or
evaporated milk. Breast-fed infants need exogenous
supplementation of similar amounts of the vitamin. Older children and adults need no supplementation if they consume adequate amounts of fish, eggs, liver, and fortified milk. Patients with renal, liver, or bowel absorption disease may require 2,000 to
5,000 units per day. For patients on anticonvulsant medications or with cystic fibrosis, especially those
with minimal exposure to sunlight, a dose of up to
2,000 units per day may be necessary.
Once rickets is overt, the disorder may be treated
with 600,000 units of vitamin D parenterally in one
or multiple doses over 24 hours, or by the use of
5,000 to 10,000 units per day orally for six to eight weeks. During treatment, the serum calcium, phos-phate, and alkaline phosphatase should be moni-tored, both for detection of possible hypocalcemia
and hypercalcemia during bone re-calcification and for evidence of complete healing, reflected in a normal serum alkaline phosphatase. Patients with
hepatic, renal glomerular disease and intestinal malabsorption may require 10,000 to 25,000 units of
vitamin D per day orally. In addition, other
bene-ficial drugs for these conditions are
dihydrotachys-terol (DHT) and i,25(OH)2D3. DHT, a sterol with
steric similarity to active vitamin D, does not
re-quire renal hydroxylation for activation.40 Its
ad-vantage lies in its short half-life (50 hours as
op-posed to at least 20 days for vitamin D) and rapid onset of action; 1 mg of DHT has at least the
equivalent effect of 3 mg of vitamin D (1 mg of
vitamin D equals 40,000 IU). Active vitamin D,
i,25(OH)2D3, is now available commercially (Ro-caltrol, Roche). Although it may be the preferred drug for any of the above conditions414, its use is currently restricted to therapy of renal osteodystro-phy. Its onset of action is rapid and its half-life is short (less than 24 hours).47 In patients with renal
osteodystrophy the currently recommended dose is 0.25 to 2 per day depending on clinical response.48 In these patients it is essential to monitor serum
calcium levels for evidence of hypercalcemia, in
addition to other chemical and radiographic param-eters.
Patients with a renal enzyme abnormality
(vi-tamin D dependent rickets) should receive 5,000 to 50,000 IU of vitamin D per day or equivalent doses
of DHT or active vitamin D.
The treatment of rickets accompanying renal
tu-bular abnormalities involves elevation of serum
phosphate levels above 4 mg/iOO ml accomplished usually by administration of i.5 to 2 gm of phos-phorus per day in divided doses.495’ Recently, phos-phate tablets have become available. Although they must stifi be dissolved in water, they are much more easily transported. Supplemental vitamin D, 25,000 to 100,000 IU, or equivalent doses of DHT or active vitamin D metabolites must also be administered to counteract the inhibition of calcium absorption by phosphate.52 In renal tubular acidosis, appro-priate doses of bicarbonate are also necessary, while both bicarbonate and potassium may be required in Fanconi syndrome.
Clearly we are again being confronted by an old illness, re-emerging in a new, more subtle form. It
is imperative that we continue to identify potential patient populations at risk, and carefully monitor those biochemical parameters necessary for early
detection of this disorder in order to facilitate prompt prophylaxis and/or therapy.
QUESTIONS AND ANSWERS
Dr Bundy: How would you advise me to follow patients with cystic fibrosis or seizure disorders who may potentially develop rickets?
Dr Lovinger: I would follow the alkaline phos-phatase level every three months. If it starts to rise, I would start vitamin D supplementation (1,000 to 2,000 units per day). Once the proper vitamin D dose is reached, the alkaline phosphatase should return to normal. Patients taking vitamin D also need their calcium levels monitored every three
months for evidence of hypercalcemia.
Dr Solomon: Could you again define the differ-ence between renal osteodystrophy and renal
tu-bular disorders?
Dr Lovinger: Renal osteodystrophy refers to rick-eta secondary to chronic renal disease. In this
dis-order patients cannot “activate” vitamin D. Thus,
it is a type 1 form of rickets. Renal tubular disorders
refer to a condition in which the kidney cannot
reabsorb adequate amounts of phosphate. The
con-dition is a type 2 form of rickets.
Dr Jaffe: I have been following a patient with biiary atresia. What is the pathogenesis of this form of rickets?
absorp-tion of fat soluble vitamins. This is one source of potential rickets. In addition, biliary atresia may
cause liver parenchymal damage which may result
in failure to hydroxylate circulating vitamin D.
Thus, both of these mechanisms may play a role in
the development of rickets.
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2. Weick MT: A history of rickets in the United States. Am J Cliii Nutr 20:1234, 1967
3. Loomis WF: Rickets. Sci Am 223:96, 1970
4. Deluca HF: The vitamin D system in the regulation of calcium and phosphorus metabolism. Nutr Rev 37:161, 1979 5. Deluca H: Vitamin D metabolism and function. Arch Intern
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5a.Canterbury JM, Gavellas G, Bourgoignie JJ, et al: Metabolic
consequences of oral administration of
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6. Harrison HE, Harrison HC: Rickets then and now. JPediatr 87:1144, 1975
7. Root AW, Harrison HE: Recent advances in calcium metab-olism, 11. Disorders ofcalcium homeostasis. JPediatr 88:77,
1976
8. Castile RG, Marks U, Stickler GB: Vtamin D deficiency rickets: 2 cases with faulty infant feeding practices. Am J Dis Child 129:984, 1975
9. Dent CE, Smith R: Nutritional osteomalacia. Quart J Med 38:195, 1968
10. Sitrin M, Meredith G, Rosenberg JH: Vitamin D deficiency
and bone disease in gastrointestinal disorders. Arch Intern Med 138: 886, 1978
11. Kobayashi A, Kawai 5, Utsonomica T, et al: Bone disease in infants and children with hepatobiiary disease. Arch Dis
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12. Daum F, Rosen JF, Roginsky M, et al: 25-Hydroxy vitamin
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biliary atresia. J Pediatr 88:1041, 1976
13. Chan JCM, Hsu A: Vitamin D metabolism and renal disease. Adv Pediatr, in press 1980
14. Chan JCM: Renal osteodystrophy in children. Clin Pediatr
15:996, 1976
15. Winnacker JL, Yeager H, Saunders JA, et al: Rickets in
children receiving anticonvulsant drugs. Am J Dis Child 131:286, 1977
16. Croseley CJ, Chu C, Berman PN: Rickets associated with
long term anticonvulsant therapy in a pediatric outpatient population. Pediatrics 56:52, 1975
17. Liakakos D, Papadopoulos Z, Vlachos P, et al: Serum
alka-line phosphatase and urinary hydroxyproline values in chil-then receiving phenobarbital with and without vitamin D. J Pediatr 87:291, 1975
18. Lifshitz F, Maclaren NK: Vitamin D dependent rickets in
institutionalized mentally retarded children receiving
long-term anticonvulsant therapy. I. A. Survey of 288 patients. J Pediatr 83:612, 1973
19. Hahn TJ, Squires AE, Haistead LR, et al: Reduced serum 25-vitamin D concentrations and disordered mineral
metab-olism in patients with cystic fibrosis. J Pediatr 94:38, 1979
20. Fraser D, Kooh SW, Kind HP, et al: Pathogenesis of
hered-itary vitamin D metabolism involving defective conversion
of 25 hydroxyvitamin D to 1,25 dihydroxyvitamin D. N Engl JMed289:817, 1973
21. Suster P, Palla JV: Pseudovitamin-D-deficiency rickets. J Pediatr 76:937, 1970
22. Arnaud C, Maijer R, Reade T, et al: Vitamin D dependency: An inherited postnatal syndrome with secondary hyperpara-thyroidism. Pediatrics 46:871, 1970
23. Brooks MH, Bell NA, Love L, et al: Vitamin D dependent
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1,25-dihydroxy-vitamin D. N EngI J Med 298:996, 1978
24. Davies DP, Hughes CA, Moore JR: Rickets in preterm infants. Arch Dis Child 53:88, 1978
25. O’Connor P: Vitamin D deficiency rickets in two breast-fed
infants who were not receiving vitamin D supplementation.
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26. Swischuk LE, Hayden CK: Seizures and demineralization of
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27. Edidin DV, Levitsky LL, Schey W, et al: Resurgence of
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36. Lightwood R: Calcium inarction of the kidney in infants.
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37. Condon JR, Nassim JR, Rutter A: Pathogenesis of rickets
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38. Chan JCM: Acid-base, calcium potassium and aldosterone metabolism in renal tubular acidosis. Nephron 23:153, 1979
39. Schulman JD, Schneider JA: Cystinosis and Fanconi
syn-drome. Pediatr Clin North Am 23:779, 1976
40. Harrison HE, Lifshitz F, Blizzard RM: Comparison between
crystalline dihydrotachysterol and calciferol in patients re-quiring pharmacologic vitamin D therapy. N EngI J Med 276:894, 1967
41. Long RG, Varghese Z, Meinhard EA, et al: Parenteral 1,25 dihydroxyvitamin D in hepatic osteomalacia. Br Med J 1:75, 1978
42. Bordier P, SingraffJ, Gueris J, et al: The effect of 1-hydroxy
vitamin D and 1,25 dihydroxyvitamin D on the bone in patients with renal osteodystrophy. Am J Med 64:101, 1978
43. Beale MG, Chan JCM, Oldham SB, et al: Vitamin D: The discovery of its metabolites and their therapeutic applica-tions. Pediatrics 57:729, 1976
44. Balsan S, Garabedian M: 1,25 Dihydroxyvitamin D and 1-hydroxyvitamin D in children: Biologic and therapeutic ef-fects of nutritional rickets and different types of vitamin D
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45. Gray RW, Caldes AE, Wilz DR, et al: Metabolism and
excretion of 3H-1,25 dihydroxyvitamin D in healthy adults.
J Clin Endocrinol Metab 46:756, 1978
46. Rosen JF, Fleischman AR, Finberg L, et al: 1,25
Dihydroxy-vitamin D: Its use in long term management of idiopathic hypoparathyroidism in children. J Clin Endocrinol Metab 45:457, 1977
47. Mawer EB, Blackshouse J, Davies M, et al: Metabolic fate
of administered 1,25 dihydroxyvitamin D in controls and patients with hypoparathyroidism. Lancet 1:1203, 1976
48. Chan JCM, DeLuca HR: Calcium and parathyroid disorders in children: Chronic renal failure and treatment with calci-ferol. JAMA 241:1242, 1979
and vitamin D to prevent dwarfism and rickets in X-linked hypophosphatemia. N Engi J Med 287:481, 1972
51. Menking M, Sotos JF: Effect ofadministration or oral neural phosphate in hypophosphatemic rickets. J Pediatr 75:1001, 1969
52. Chan JCM, Bartter FC: Hypophosphatemic rickets: Effects
of la,25 dihydroxyvitamin D on growth and mineral
metab-olism. Pediatrics 64:488, 1979
53. Hirschman GH, DeLuca HF, Chan JCM:
Hypophospha-temic vitamin D resistant rickets: Metabolic balance studies
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ascorbic acid. Pediatrics 61:451, 1978
CHARLES DICKENS DESCRIBES HIS IMPRESSION OF THE CHILDREN AT
THE PERKINS INSTITUTION FOR THE BLIND
In his American Notes, published in 1843, Dickens vividly described his six
months’ visit to the United States between January and June 1842. None of the
public institutions that he visited made a more favorable impression on him than the Perkins Institution for the Blind, located in Boston.
He wrote:
I went to see this place [the Perkins Institution] one very fine winter morning: an Italian sky above, and the air so clear and bright on every side, that even my eyes, which
are none of the best, could follow the minute lines and scraps of tracery in distant buildings. Like most other public institutions in America, of the same class, it stands a
mile or two without the town, in a cheerful, healthy spot; and is an airy, spacious, handsome edifice.
The children were at their daily tasks in different rooms, except a few who were already dismissed, and were at play. Here, as in many institutions, no uniform is worn; and I was very glad of it, for two reasons. Firstly, because I am sure that nothing but senseless custom and want of thought would reconcile us to the liveries and badges we
are so fond of at home. Secondly, because the absence of these things presents each child to the visitor in his or her own proper character, with its individuality unimpaired-not lost in a dull, ugly, monotonous repetition of the same unmeaning garb, which is really an important consideration.
The wisdom of encouraging a little harmless pride in personal appearance even among the blind, or the whimsical absurdity of considering charity and leather breeches inseparable companions, as we do, requires no comment.
Good order, cleanliness, and comfort pervaded every corner of the building. The various classes, who were gathered round their teachers, answered the questions put to them with readiness and intelligence, and in a spirit of cheerful contest for precedence which pleased me very much. Those who were at play were gleesome and noisy as other children. More spiritual and affectionate friendships appeared to exist among them than would be found among other young persons suffering under no deprivation; but this I expected and was prepared to find. It is a part of the great scheme of Heaven’s merciful consideration for the afflicted.
REFERENCE
Noted by T.E.C., Jr., MD
