Table 1 Characteristics of the three cases at presentation

 Age

6 months

6 months

5 months

 Ethnicity

South African-Ghanaian

Somali

British Pakistani

 Month of presentation

January

February

February

 Presenting feature

Cardiac arrest at home; down time of 36 min

Respiratory arrest and seizure; apnoea (~ 4 min)

Cough, difficulty breathing and poor feeding

 Feeding mode at presentation

Exclusively breastfed

Breastfed (solids started 2 weeks earlier)

Exclusively breastfed

 Birth weight in kg (centile)

3.7 (91st)

4.0 (98th)

1.75 at 35 weeks (9th)

 Development

Normal

Normal

Normal

 Immunisation

Up to date

Up to date

Up to date

 Length cm (centile)

68 (50th)

71 (91st)

58 (0.4th)

 Weight kg (centile)

8 (50th)

8.5 (91st)

4.5 (<  0.4th)

 Adjusted serum Calcium (2.2–2.7 mmol/L)^b

1.60

1.22

1.96

 PO₄ (1.3–2.4 mmol/L)

0.47^a

1.95

0.69

 ALP (105–420 IU/L)

802

996

1391

 PTH (12–29 ng/L)

167

219

482

 25OHD (>  50 nmol/L)

< 15

5.2

12.5

 X-ray knee

Fraying and splaying of the metaphyses characteristic of rickets

Fraying and splaying of the metaphyses characteristic of rickets

Fraying and splaying of the metaphyses characteristic of rickets

 ECG - QTc (< 450 ms)

547

485

455

 Echocardiography

Dilated CMP

Dilated CMP

Dilated CMP

  LV dimension in diastole (Z-score)

+4.6

+ 5.5

+ 6.5

  LV EF (range: 55–70%)

25–30%

29%

25%

  LV FS (range: 29–40%)

7%

7%

15%

  Function

Global hypokinesia

Global hypokinesia

Global hypokinesia

  Mitral regurgitation (MR)

Severe MR

Moderate MR

Severe MR

  Structural defects

None

None

None

 Multivitamin taken during pregnancy

Yes

Yes

No

 Adjusted serum Calcium (2.2–2.6 mmol/L)^b

2.42

2.31

2.25

 PO₄ (0.8–1.5 mmol/L)

1.18

1.29

1.1

 ALP (25–105 IU/L)

77

161

86

 PTH (15–65 ng/L)

54

91

87

 25OHD (>  50 nmol/L)

33.1

19.8

24