Characteristics and outcomes of Bahraini pediatric patients sent abroad for bone marrow transplantation: A ten-year retrospective cohort study

Table 1 Clinical characteristics of pediatric patients who underwent bone marrow transplantation, n (%)/mean ± SD/ median (25^th-75^th percentiles)

Patient demography	Total, n = 62 (100)	Allogeneic, n = 48/61 (77.4)	Autologous, n = 13/61 (21.0)	P value (95%CI)
Sex				0.5471
Male	33 (53.2)	27 (56.3)	6 (46.2)
Female	29 (46.8)	21 (43.8)	7 (53.8)
Governorate				0.3772
Northern	26 (41.9)	17 (35.4)	8 (61.5)
Capital	15 (24.2)	13 (27.1)	2 (15.4)
Muharraq	11 (17.7)	9 (18.8)	2 (15.4)
Southern	10 (16.1)	9 (18.8)	1 (7.7)
Age at diagnosis (year)	5.6 ± 4.8	5.4 ± 5.0	5.8 ± 4.0	0.7873 (-2.6, 3.4)
Age group at diagnosis (year)				0.8472
0-5	33 (53.2)	27 (56.3)	6 (46.2)
6-10	20 (32.3)	14 (29.2)	5 (38.5)
11-15	8 (12.9)	6 (12.5)	2 (15.4)
> 15	1 (1.6)	1 (2.1)	0 (0.0)
Age at transplant (year)	7.8 ± 4.9	7.8 ± 5.1	7.2 ± 4.3	0.6933 (-3.7, 2.5)
Age group at transplant (year)				0.5742
0-5	25 (40.3)	21 (43.8)	4 (30.8)
6-10	21 (33.9)	15 (31.3)	6 (46.2)
11-15	13 (21.0)	9 (18.8)	3 (23.1)
> 15	3 (4.8)	3 (6.3)	0 (0.0)
Weight at transplant (kg), (n = 48)	19.1 (12.0-29.8)	19.1 (12.3-29.7)	20.6 (10.7-27.6)	0.7754
Height at transplant (cm), (n = 47)	115.8 ± 30.1	116.6 ± 29.1	113.5 ± 34.1	0.7623 (-23.6, 17.4)
Body mass index, (n = 49)	16.0 (14.4-18.0)	15.9 (14.1-17.9)	16.6 (15.1-17.0)	0.4154
Presence of associated diseases5	29 (46.8)	21 (43.8)	7 (53.8)	0.5471
Previous bone marrow biopsy	35 (56.5)	25 (52.0)	10 (76.9)	0.1281
Number of bone marrow aspirate, (n = 35)	2.0 (1.0-3.0)	2.0 (1.0-3.0)	2.0 (1.0-2.0)	0.1623
Family history of similar condition, (n = 34)	14 (41.2)	13 (27.1)	1 (7.7)	0.1021
Follow-up duration (year)	3.3 ± 2.5	3.41 ± 2.50	2.98 ± 2.42	0.5773 (-1.9, 1.1)
Number of overseas visits	1.0 (1.0-2.0)	1.0 (1.0-2.0)	1.0 (1.0-2.0)	0.9494

¹Fisher’s exact test.

²Pearson’s χ² test.

³Student’s t-test.

⁴Mann-Whitney U test.

⁵Supplementary Table 1.

Table 2 Indications of bone marrow transplantation in Bahraini pediatric patients, n (%)

Indications of bone marrow transplantation1	Total, n = 62 (100.0)	Allogeneic, n = 48/61 (77.4)	Autologous, n = 13/61 (21.0)	P value1
Oncological indications	41 (66.1)	27 (56.3)	13 (100.0)	0.002
Acute myeloid leukemia	15 (36.6)	14 (29.2)	0 (0.0)	0.028
Acute lymphoblastic leukemia	11 (26.8)	11 (22.9)	0 (0.0)	0.099
Neuroblastoma	7 (17.1)	0 (0.0)	7 (53.8)	< 0.0001
Hodgkin’s lymphoma	4 (9.8)	1 (2.1)	3 (23.1)	0.028
Wilms tumor	2 (4.9)	0 (0.0)	2 (15.4)	0.043
Mixed germ cell tumor	1 (2.4)	0 (0.0)	1 (7.7)	0.213
Hemophagocytic lymphohistiocytosis	1 (2.4)	1 (2.1)	0 (0.0)	1.000
Hematological indications	21 (33.9)	19 (39.6)	0 (0.0)	0.006
Aplastic anemia	9 (42.3)	8 (16.7)	0 (0.0)	0.184
Beta thalassemia major	5 (23.8)	5 (10.4)	0 (0.0)	0.575
Myelodysplastic syndrome	2 (9.5)	2 (4.2)	0 (0.0)	1.000
Fanconi anemia	2 (9.5)	1 (2.1)	0 (0.0)	1.000
Diamond Blackfan anemia	1 (4.8)	1 (2.1)	0 (0.0)	1.000
Hemoglobin H disease	1 (4.8)	1 (2.1)	0 (0.0)	1.000
Sickle cell disease	1 (4.8)	1 (2.1)	0 (0.0)	1.000
Immunological indications	7 (11.3)	7 (14.6)	0 (0.0)	0.328
Severe combined immunodeficiency	5 (71.4)	5 (10.4)	0 (0.0)	0.575
Chronic granulomatous disease	1 (14.3)	1 (2.1)	0 (0.0)	1.000
X-linked agammaglobulinemia	1 (14.3)	1 (2.1)	0 (0.0)	1.000

¹Fisher’s exact test.

Table 3 Complications after first and second bone marrow transplantation, n (%)

Complications2	Total BMTs, n = 64/68 (94.1)	Allogeneic, n = 51/52 (79.7)	Autologous, n = 13/15 (86.7)	P value1
Infectious
URTI	36 (56.3)	31 (60.8)	5 (38.5)	0.086
CMV reactivation	16 (25.0)	15 (29.4)	1 (7.7)	0.095
Gastroenteritis	16 (25.0)	12 (23.5)	4 (30.8)	0.743
Sepsis	14 (21.9)	12 (23.5)	2 (15.4)	0.719
Colitis	11 (17.2)	8 (15.7)	3 (23.1)	0.699
Cytokine release syndrome	9 (14.1)	9 (17.7)	0 (0.0)	0.191
Conjunctivitis	9 (14.1)	7 (13.7)	2 (15.4)	1.000
Coronavirus	7 (10.9)	6 (11.8)	1 (7.7)	1.000
Otitis media	7 (10.9)	4 (7.8)	3 (23.1)	0.181
Tonsilitis	6 (9.4)	5 (9.8)	1 (7.7)	1.000
BK virus-induced hemorrhagic cystitis	6 (9.4)	6 (11.8)	0 (0.0)	0.325
Epstein-Barr virus reactivation	5 (7.8)	5 (9.8)	0 (0.0)	0.580
Pneumonia	5 (7.8)	3 (5.9)	2 (15.4)	0.310
Viral warts	5 (7.8)	4 (7.8)	1 (7.7)	1.000
Otitis externa	4 (6.3)	3 (5.9)	1 (7.7)	1.000
Adenovirus reactivation	4 (6.3)	3 (5.9)	1 (7.7)	1.000
Sinusitis	4 (6.3)	4 (7.8)	0 (0.0)	0.568
Cellulitis	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Chronic gingivitis	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Acute gingivitis	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Herpes zoster	3 (4.7)	2 (3.9)	1 (7.7)	0.539
Others3	39 (60.9)	35 (68.6)	4 (30.8)	0.007
Non-infectious
Mucositis	37 (57.8)	29 (56.9)	8 (61.5)	1.000
Acute GvHD	20 (31.3)	20 (39.2)	0 (0.0)	0.003
Neutropenia	20 (31.3)	12 (23.5)	8 (61.5)	0.051
Disease relapse	18 (28.1)	11 (21.6)	7 (53.8)	0.094
Chronic GvHD	12 (18.8)	12 (23.5)	0 (0.0)	0.055
Skin rash	9 (14.1)	9 (17.7)	0 (0.0)	0.191
Unspecified skin changes/disorder	9 (14.1)	8 (15.7)	1 (7.7)	0.671
Gastritis	9 (14.1)	8 (15.7)	1 (7.7)	0.671
Acute kidney injury	8 (12.5)	8 (15.7)	0 (0.0)	0.183
Electrolyte imbalance	7 (10.9)	5 (9.8)	2 (15.4)	0.649
Dental caries	7 (10.9)	7 (13.7)	0 (0.0)	0.335
New malignancy	5 (7.8)	4 (7.8)	1 (7.7)	1.000
Leukopenia	4 (6.3)	4 (7.8)	0 (0.0)	0.568
Thrombocytopenia	4 (6.3)	4 (7.8)	0 (0.0)	0.568
Impetigo	4 (6.3)	4 (7.8)	0 (0.0)	0.568
Amenorrhea	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Appendicitis	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Cushing’s syndrome	3 (4.7)	2 (3.9)	1 (7.7)	0.539
Short stature	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Allergic rhinitis	3 (4.7)	1 (1.9)	2 (15.4)	0.123
Hypertension	3 (4.7)	3 (5.9)	0 (0.0)	1.000
Recurrent oral aphthae	3 (4.7)	2 (3.9)	1 (7.7)	0.539
Others4	61 (95.3)	48 (94.1)	13 (100.0)	0.609

¹Fisher’s exact test.

²Some patients developed more than one complication. Data are presented as numbers and percentages.

³Supplementary Table 3.

⁴Supplementary Table 4.

BMTs: Bone marrow transplantation; URTI: Upper respiratory tract infection; CMV: Cytomegalovirus; GvHD: Graft-versus-host disease.

Table 4 Analysis of outcome in pediatric first bone marrow transplantation, n (%)/mean ± SD/ median (25^th-75^th percentiles)

Variable	Survived, n = 48 (77.4)	Died, n = 14 (22.6)	P value (95%CI)
Sex			1.0001
Male	26 (54.2)	7 (50)
Female	22 (45.8)	7 (50)
Area of residence			0.1142
Northern	17 (35.4)	9 (64.3)
Capital	14 (29.2)	1 (7.1)
Southern	9 (18.8)	1 (7.1)
Muharraq	8 (16.7)	3 (21.4)
Age at BMT (year)	7.9 ± 5.0	7.4 ± 4.6	0.772 (-2.6-3.4)3
Age group at BMT			0.8202
0-5	19 (76.0)	6 (24.0)
6-10	16 (76.2)	5 (23.8)
11-15	10 (76.9)	3 (23.1)
> 15	3 (100)	0 (0.0)
Weight at transplant (kg), (n = 48)	21.2 (12.3-29.7)	18.1 (8.8-24.6)	0.2804
Height at transplant (cm), (n = 47)	116.8 ± 28.8	110.9 ± 37.8	0.619 (-17.8-29.6)3
Body mass index, (n = 49)	16.0 (14.4-18.6)	16.0 (15.4-17.0)	0.5854
Presence of associated diseases	24 (50.0)	5 (35.7)	0.3801
Type of graft (n = 61)			1.0001
Autologous	10 (20.8)	3 (23.1)
Allogeneic	38 (79.2)	10 (76.9)
Donor-recipient relationship (n = 61)			0.8632
Related donors	37 (77.1)	10 (76.9)
Patients themselves	10 (20.8)	3 (23.1)
Unrelated donors	1 (2.1)	0 (0.0)
Indications of BMT
Acute myeloid leukemia	8 (16.7)	7 (50.0)	0.0281
Other indications	40 (83.3)	7 (50.0)
Post-BMT complications (n = 58)	45 (95.7)	13 (100.0)	1.0001
BMT countries			0.0382
Middle East	43 (89.6)	9 (64.3)
Other countries	5 (10.4)	5 (35.7)
Follow-up duration (year)	3.9 ± 2.3	0.8 ± 1.3	< 0.0001 (2.1-4.1)3

¹Fisher’s exact test.

²Pearson’s χ² test.

³Student’s t-test.

⁴Mann-Whitney U test.

BMT: Bone marrow transplantation.

Table 5 Univariate and multivariate analysis of the selected predictors of outcome of pediatric bone marrow transplantation

Variable	Univariate analysis		Multivariate analysis
	Odds ratio (95%CI)	P value	Odds ratio (95%CI)	P value
Male sex	0.846 (0.257-2.786)	0.783	0.819 (0.093-7.184)	0.857
Governorate (Northern vs others)	3.282 (0.947-11.376)	0.061	4.415 (0.248-78.607)	0.312
Age at BMT (year)	0.821 (0.411-1.460)	0.577	1.481 (0.658-3.331)	0.342
Age group (0-5 years vs others)	1.145 (0.343-3.825)	0.826	1.081 (0.013-93.501)	0.973
Weight at BMT (kg)	0.965 (0.900-1.034)	0.307	0.863 (0.512-1.455)	0.581
Height at BMT (cm)	0.993 (0.968-1.019)	0.611	0.982 (0.819-1.179)	0.849
Body mass index (kg/m2)	0.858 (0.692-1.064)	0.164	0.850 (0.324-2.230)	0.741
Presence of associated diseases	1.800 (0.526-6.164)	0.349	2.841 (0.343-23.518)	0.333
Type of graft (allogeneic vs autologous)	1.140 (0.263-4.940)	0.861	4.532 (0.330-62.245)	0.258
Indication (AML vs others)	5.000 (1.371-18.232)	0.015	21.556 (0.719-646.242)	0.077
Presence of complications	1.154 (0.111-12.048)	0.905	0.000 (0.000-0.000)	0.999
BMT countries (Middle East vs others)	4.778 (1.140-20.020)	0.032	0.463 (0.034-6.300)	0.563

BMT: Bone marrow transplantation; AML: Acute myeloid leukemia.