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deformities. Therefore, early diagnosis and optimal therapy with oral alkali,

either as bicarbonate or citrate, is recommended. However, citrate is preferred

over bicarbonate as it is better tolerated. The recommended dose is 1–2 mEq/

Kg daily in divided doses in distal RTA and 10–20 mEq/Kg daily in proximal

RTA (higher dose required due to massive urinary loss of bicarbonate). Short-

term administration of potassium, calcitriol, and phosphate may be required

in these patients. Correction of acidosis not only improves hypokalemia and

hypercalciuria but also leads to increased 1,25(OH) 2 D synthesis. Therefore,

long-term use of calcitriol is not required in patients with RTA. In addition, it

may worsen hypercalciuria in patients with distal RTA. Overtreatment with

alkali should be avoided as it may worsen hypokalemia and hypercalciuria.

During follow-up, serum potassium, pH, bicarbonate, and urinary calcium

should be periodically monitored. In addition, renal ultrasonography should

also be performed to detect nephrocalcinosis. The oral alkali preparations

commonly used in the management of RTA are summarized in the table given

below.

Preparation Composition Alkali content Potassium content

Potassium citrate and

citric acid syrup

Each 5 ml contains

Potassium citrate 1100 mg

2 mEq base/ml 5 mEq potassium/

ml

Citric acid 334 mg

Shohl’s solution Each litre contain citric

acid 140 g

1 mEq base/ml −

Hydrated crystalline

sodium citrate 90 g

Sodium bicarbonate

tablets

325 mg/tablet 325 mg tablet

contains 4 mEq

−

or

650 mg/ tablet 650 mg tablet

contains 8 mEq

78. What are the endocrine causes of exuberant callus formation?

The exuberant callus formation is the characteristic feature of osteogenesis

imperfecta, glucocorticoid excess (exogenous or endogenous), Charcot’s

arthropathy, renal osteodystrophy, and multiple myeloma. The mechanism of

exuberant callus formation remains elusive. However, unrestrained production

of collagen by the osteoblast in response to poorly mineralized matrix (callus)

possibly explains this phenomenon (Fig. 5.16).

5 Rickets–Osteomalacia