Reference Intervals for Common Renal and Liver Function Clinical Chemistry Parameters Among Apparently Healthy Pregnant and Non-pregnant Women in South Wollo Zone, Amhara National Regional State, Northeast Ethiopia

Figures & data

Table 1 Methods Used (Traceability) and Analytical Precisions for Selected Assays

Analyte	Method	Unit	APHLDB within-run Precision		Manufacturer’s within-run Precision		APHLDB Between-run Precision		Manufacturer’s Between-run Precision
			Mean	%CV	Mean	%CV	Mean	%CV	Mean	%CV
Albumin	Bromocresol green-succinate buffer	g/L	4.4	0.06	4.5	1.2	4.2	1.3	4.5	1.6
Total protein	Biuret/endpoint	g/L	51.4	1.1	51.8	1.0	51.1	0.9	51.8	1.1
AST	IFCC Modified without pyridoxal phosphate	U/L	47.6	0.41	38	1.4	47.3	5.3	38	5.9
ALT	IFCC modified without pyridoxal phosphate	U/L	40	1.6	43	1.8	40.5	4.9	43	5.3
ALP-DEA	p-Nitrophenyl phosphate. Diethanolamine	U/L	110	1.0	117	1.1	110.3	4.2	117	4.5
Bilirubin (direct)	Dizotizedsulfanilic	mg/dL	0.85	0.8	0.77	1.2	0.86	1.5	0.77	2.3
Bilirubin (total)	Dizotizedsulfanilic	mg/dL	2.13	2.1	0.59	3.0	2.09	3.8	0.59	3.6
Urea	Enzymatic-UV kinetic	mg/dL	26.2	2.9	42	3.3	26.4	4.2	42	4.3
Creatinine	Jaffe-kinetic	mg/dL	1.65	2.6	1.7	2.9	1.63	3.0	1.7	3.9

Table 2 Sociodemographic Characteristics of Study Participants from S Wollo Zone, Northeast Ethiopia, 2019

Variables	Pregnant		Non-Pregnant
Age in years	Number	%	Number	%
16–20	6	3.6	26	16.4
21–29	115	69.6	83	52.5
30–39	39	23.6	32	20.2
40–60	5	3.0	15	9.4
Marital status
Single	5	3.1	81	51.2
Married	160	96.9	77	48.8
Pregnancy status
Primgravida	51	30.9	NA	NA
Multigravida	114	69.1	NA	NA
Occupation
Employed	23	14.5	25	15.8
Housewife	92	55.7	43	27.2
Students	3	1.8	34	21.5
Others	47	30.3	56	35.4
Religion
Muslim	96	58.1	97	61.3
Orthodox	60	36.3	56	35.4
Others	9	5.6	5	3.2
Educational status
Illiterate and elementary completed	109	66.1	95	60.1
High school completed and above	56	33.9	63	39.9
Residence
Urban	118	71.5	102	64.6
Rural	47	28.5	56	35.4

Note: %: percentage.

Table 3 The Calculated Mean, Median, 95%CI for Mean and 2.5th–95th Percentile RI of Common Liver and Renal Function Tests in Relation to Pregnancy Status of Healthy Adult Women in South Wollo Zone, Amhara National Regional State, Northeast Ethiopia, 2019

Parameters	Unit	Pregnant				Non-pregnant				P-value	Combined Pregnant and Non-pregnant
		Mean	Median	95%CI for Mean	2.5th–97.5th Percentile Range (RI)	Mean	Median	95%CI for Mean	2.5th–97.5th Percentile Range (RI)		Mean	Median	95%CI for mean	2.5th–97.5th Percentile Range (RI)
Albumin*	g/L	34.1	34.11	33.4–34.7	26.1–42.8	41.5	41.8	40.9–42.1	32.8–47.8	0.0001	37.5	37.9	36.9–38.1	26.6–46.9
T. protein*	g/L	62.0	62.0	60.9–63.1	48.5–74.7	71.8	72.0	70.8–72.9	56.7–83.9	0.0001	66.7	67.7	65.7–67.6	49.4–82.3
AST (SGOT)	U/L	18.8	16.8	17.2–20.3	2.4–43.6	20.8	19.2	19.0–21.7	4.2–37.1	0.151	19.6	17.9	15.5–20.6	2.9–42.1
ALT (SGPT)	U/L	13.5	12.1	12.4–14.4	0.9–28.3	17.6	16.0	16.1–19.1	2.6–41.1	0.052	14.7	13.7	13.9–15.5	1.5–31.4
ALP-DEA*	U/L	171	157	157.9–184.3	21.2–337	142.0	138	131.6–152.5	3.2–278.4	0.045	157.1	146.0	148.6–165.6	8.8–320
Bilirubin (direct)	mg/dL	0.17	0.16	0.14–0.19	0.03–0.32	0.19	0.18	0.17–0.21	0.06–0.38	0.205	0.17	0.18	0.15–0.19	0.04–0.36
Bilirubin (total)	mg/dL	0.6	0.64	0.58–0.63	0.26–0.94	0.58	0.61	0.55–0.62	0.24–1.06	0.227	0.59	0.63	0.57–0.61	0.24–0.96
Urea*	mg/dL	13.0	12.5	12.4–13.6	7.1–20.8	16.8	16.4	16.0–17.5	8.0–27.8	0.0001	14.7	14.5	14.2–15.2	7.5–24.9
Creatinine*	mg/dL	0.58	0.6	0.56–0.60	0.29–0.87	0.73	0.73	0.71–0.75	0.44–1.00	0.0001	0.65	0.66	0.63–0.67	0.33–0.97

Note: *Parameters with statistically significant differences based on pregnancy status.

Abbreviations: ALT, alanine aminotransferase; ALP-DEA, alkaline phosphatase-diethanolaine buffer; AST, aspartate aminotransferase; CI, confidence interval; dL, deciliter; g, gram; L, liter; mg, milligram; SGOT, serum glutamate oxaloacetate transaminase; SGPT, serum glutamate pyruvate transaminase; U, unit.

Table 4 95%CI for Upper and Lower Reference Limits of Common Liver and Renal Function Clinical Chemistry Tests of Healthy Pregnant and Non-pregnant Women in S Wollo Zone Amhara National Regional State, Northeast Ethiopia, 2019

Analytes	Unit	Pregnancy Status	RI Percentile (Range)	Lower Reference Limit 95%CI	Upper Reference Limit 95%CI
Albumin	g/L	Combined	26.6–46.9	(26.1–27.46)	(46.3–47.7)
		Pregnant	26.1–42.8	(24.0–27.06)	(41.8–46.02)
		Non-pregnant	32.8–47.8	(31.85–35.23)	(46.95–49.26)
T. protein	g/L	Combined	49.4–82.3	(48.52–51.6)	(80.86–84.47)
		Pregnant	48.5–74.7	(41.2–50.77)	(72.73–77.07)
		Non-pregnant	56.7–83.9	(55.84–60.17)	(81.48–87.54)
AST (SGOT)	U/L	Combined	2.9–42.1	(0.89–6.25)	(39.05–43.83)
		Pregnant	2.4–43.6	(0–4.84)	(40.76–45)
		Non-pregnant	4.2–37.1	(0.89–8.6)	(34.41–43.83)
ALT (SGPT)	U/L	Combined	1.5–31.4	(0.6–3.46)	(30.07–32.38)
		Pregnant	0.9–28.3	(0–3.18)	(25.87–31.0)
		Non-pregnant	2.6–41.1	(0–4.76)	(36.75–42.2)
ALP-DEA	U/L	Combined	8.8–320	(3.14–35.0)	(304–329)
		Pregnant	21.2–337	(3–37)	(316–404)
		Non-pregnant	3.2–278.4	(0–30)	(249–307)
Bilirubin (direct)	mg/dL	Combined	0.04–0.36	(0.02–0.50)	(0.31–0.42)
		Pregnant	0.03–0.32	(0–0.08)	(0.29–0.37)
		Non-pregnant	0.06–0.38	(0.01–0.12)	(0.31–0.45)
Bilirubin (total)	mg/dL	Combined	0.24–0.96	(0.15–0.26)	(0.9–1.0)
		Pregnant	0.26–0.94	(0.14–0.29)	(0.9–0.96)
		Non-pregnant	0.24–1.06	(0.12–0.28)	(0.99–1.11)
Urea	mg/dL	Combined	7.5–24.9	(6.28-8.13)	(23.28–26.34)
		Pregnant	7.1–20.8	(3.83-7.90)	(19.5-23.95)
		Non-pregnant	8.0–27.8	(5.08-10.14)	(25.3-29.18)
Creatinine	mg/dL	Combined	0.33–0.97	(0.34-0.44)	(0.86-0.99)
		Pregnant	0.29–0.87	(0.23-0.39)	(0.75-0.91)
		Non-pregnant	0.44–1.00	(0.41-0.51)	(0.93-1.04)

Table 5 Comparison of Common RFT and LFT RIs of Healthy Non-pregnant Women in S. Wollo Zone, Amhara National Regional State, Northeast Ethiopia with Manufacturer RIs and Other Similar Studies

Analyte	Unit	Manufacturer (APHIDB) Used RI	RI of Current Study	Northwest Ethiopia ^10	Southwest Ethiopia^Citation15	Amhara Region^Citation16	Middle Belt of Ghana^Citation17	Zimbabwe^Citation18	Eastern & South Africa^Citation6	USA (GH)^Citation19	Hong Kong (China)^Citation20
Albumin	g/L	35–50	32.8–47.8	NA	NA	36–61	33.5–50.4	41–55	35–52	35–55	37.6–48.6
Total protein	g/L	60–83	56.7–83.9	53.2–86.0	76–80	56–94.7	55.2–86.9	68–94	58–88	55–80	63.5–79.0
AST (SGOT)	U/L	0–40	4.2–37.1	6.0–32.1	12.0–59.9	10.0–43.8	13–48	12–40	14–60	0–35	11–26
ALT (SGOT	U/L	0–41	2.6–41.1	3.0–30.0	10.1–54.0	4.3–37.0	6–51	5–35	8–61	0–35	7–39
ALP-DEA	U/L	0–270	3.2–278.4	40.0–236	70.4–384.4	89.0–381	82–293	39–131	48–164	NA	36–105
Bilirubin (direct)	mg/dL	0–0.2	0.06–0.38	0.01–0.71	NA	0.01–0.49	0.04–0.2	0.0–0.3	0.02–0.51	0.1–0.3	NA
Bilirubin (total)	mg/dL	0–2	0.24–1.06	0.21–2.19	NA	0.08–0.91	0.15–1.5	0.2–1.1	0.16–2.16	0.3–1.0	0.2–0.9
Urea	mg/dL	15–39	8.0–27.8	NA	NA	10.0–38	5.4–32.4	3.9–15.4	NA	10–20	11.5–32.0
Creatinine	mg/dL	0.5–1.2	0.44–1.00	0.24–1.08	0.32–1.32	0.47–1.09	0.53–1.24	0.5–1.1	0.53–1.23	0–1.5	0.6–0.93

Note: ^aEastern and Southern Africa: Rwanda, Uganda, Kenya, and Zambia.

Abbreviations: ALT, alanine aminotransferase; ALP-DEA, alkaline phosphatase-diethanolaine buffer; AST, aspartate aminotransferase; dL, deciliter; g, gram; L, liter; mg, milligram; RI, reference interval; SGOT, serum glutamate oxaloacetate transaminase; SGPT, serum glutamate pyruvate transaminase; U, unit; APHIDB, Amhara Public Health Institute Dessie branch.

Table 6 OOR (N) and OOR (%) of Current RI Study as Compared to APHIDB Used RI (Adopted from Leaflet)

Analyte	Unit	Pregnancy Status	DRHRL Adopted RI	Current Study RI	OOR (N)	OOR (%)
Albumin	g/L	Pregnant	35–50	26.1–42.8	99	60
		Non-pregnant	35–50	32.8–47.8	38	24
Total protein	g/L	Pregnant	60–83	48.5–74.7	55	35.7
		Non-pregnant	60–83	56.7–83.9	6	3.7
AST	U/L	Pregnant	0–40	2.4–43.6	7	4.2
		Non-pregnant	0–40	4.2–37.1	4	2.5
ALT	U/L	Pregnant	0–41	0.9–28.3	11	6.6
		Non-pregnant	0–41	2.6–41.1	3	1.8
ALP-DEA	U/L	Pregnant	0–270	21.2–337	28	16.9
		Non-pregnant	0–270	3.2–278.4	4	2.5
Bilirubin (direct)	mg/dL	Pregnant	0–0.2	0.03–0.32	39	23.6
		Non-pregnant	0–0.2	0.06–0.38	48	29
Bilirubin (total)	mg/dL	Pregnant	0–2	0.26–0.94	16	9.6
		Non-pregnant	0–2	0.24–1.06	8	4.8
Urea	mg/dL	Pregnant	15–39	7.1–20.8	114	69
		Non-pregnant	15–39	8.0–27.8	84	53
Creatinine	mg/dL	Pregnant	0.5–1.2	0.29–0.87	51	30.9
		Non-pregnant	0.5–1.2	0.44–1.00	12	7.5

Abbreviations: OOR, out-of-range; N, number; %, percentage.

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