Nitroblue Tetrazolium Test in Patients with Sickle-cell Anemia T A K E S H I WAJIMA,
M.D.
Sickle Cell Center, Department of Medicine, University of Tennessee College of Medicine, Memphis, Tennessee 38163
ABSTRACT
I T IS W E L L K N O W N that patients who have sickle-cell anemia often are abnormally susceptible to bacterial infection, particularly with Pneumococcus, Meningococcus, and Salmonella. T h e neutrophilic leukocyte is one of the important factors in the host's defense mechanism against bacterial invasion. Dimitrov and associates2 reported that neutrophils from patients who had sicklecell anemia and histories of infection possess a metabolic defect that probably interferes with the destruction of material ingested during phagocytosis. Park and colleagues 6 found that normal neutrophilic leukocytes are capable of spontaneously reducing the dye nitroblue tetrazolium (NBT). T h e percentage of
neutrophils reducing the dye in vitro was shown to increase markedly in febrile states and/or leukocytosis induced by bacterial infection, provided the leukocytes were metabolically normal. 3 ' 4,6,7 False-negative results have been reported to occur in N B T tests of sickle-cell anemia patients who have meningococcal meningitis or Salmonella osteomyelitis 4 and sickle-cell crisis.1 However, there has been no study of the reliability of the N B T test in sickle-cell anemia with infection. Sickle-cell anemia patients in painful crisis with and without bacterial infections, and those in a steady state, were examined to evaluate the usefulness of the N B T test.
Received August 22, 1974; received revised manuscript March 24, 1975; accepted for publication March 24, 1975. Supported by USPHS Grant HL15169 and HL07275. Address reprint requests to Dr. Wajima at his present address: Veterans Administration Hospital, 1030 Jefferson Avenue, Memphis, Tennessee 38104.
Blood samples for the N B T test were obtained from 44 patients who had sicklecell anemia (Hb SS). Their ages ranged from 18 to 36 years. Thirteen were in vasoocclusive painful crisis with bacterial infection, nine had bacterial infection without
608
Materials and Methods
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
Wajima, Takeshi: Nitroblue tetrazolium test in patients with sickle-cell anemia. Am J Clin Pathol 64: 608-612, 1975. Forty-four patients who had sickle-cell anemia were examined to evaluate the reliability and usefulness of the nitroblue tetrazolium (NBT) test. T h e patients with sickle-cell anemia in painful crisis with bacterial infection often had low percentages of N B T reduction or negative results. T h e NBT test did not differentiate well between sickle-cell anemia with bacterial infection and without bacterial infection. (Key words: Nitroblue tetrazolium (NBT) test; Sicklecell anemia; Infection.)
November 1975
NBT TEST IN SICKLE-CELL ANEMIA
609
"Spontaneous" NBT Test
19,100 18,150 18,100 17,200 15,400 13,500 13,500 12,950 12,100 11,600
101.2 102.0 101.6 101.0 99.8 99.2 99.6 99.4 100.0 100.8
7 4 12 10 8 0 3 9 10 5 6.8 2.97
42 36 38 49 48 34 20 33 52 40 39.2 9.38
NBT solution, 0.1 ml., was mixed with 0.1 ml. of heparinized blood and incubated for 30 minutes at 37 C. Smears of the mixture were made, air-dried, and stained with Wright's stain. One hundred neutrophils were counted. MEAN S.D. T h e cells containing discrete intracellular, large, irregularly-shaped deposits were considered positive. Results were excubated for 30 minutes at 37 C. NBT pressed as percentages positive after solution, 0.1 ml., was added, and then the counting 100 neutrophils. N B T test was performed as described above. In-vitro Stimulated NBT Test Results Stimulant solution (bacterial extract), For the 16 healthy controls, the mean 0.05 ml., was mixed with 0.05 ml. of heparinized blood and the mixture was in- spontaneous N B T score was 9.12 ± 7.98%
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
Table 1. Results of N B T Tests during painful crisis, ten had vaso-occlusive crisis Steady-state Sickle-cell Anemia without any evidence of infection, and 12 were in a steady state. NBT Positive T h e presence of a bacterial infection was Corrected (%) Total documented in each instance by culture of Sponthe appropriate material (sputum, urine, Leukocyte Temperature (F.) taneous Stimulated Count vaginal discharge, or blood), response to 28* 99.8 2 16,600 antibiotics, and chest x-ray where indi99.2 2 22 15,100 cated. T h e clinical data are summarized in 8 50 14,900 99.2 Tables 1-4. 6 28 14,200 98.6 14 40 99.4 13,800 T h e vaso-occlusive painful crisis of 0 20 13,800 99.0 sickle-cell anemia was defined as an epi4 29 13,200 99.0 44 6 13,160 sode of acute pain, fever, and vascular 99.2 7 42* 13,000 99.6 obstruction produced by sickled erythro24 4 11,900 99.0 cytes that could not be explained in any 11,860 98.8 33 6 other basis. 11,000 28 10 98.6 32.3 M E A N 5.75 T h e steady state was defined as the status S.D. 4.84 9.52 of a sickle-cell anemia patient during the * Leg ulcer--not infected. intervals between febrile, painful crises, when acute symptoms and fever were Table 2. Results of NBT Tests during Sickleabsent, but chronic anemia persisted. 5 cell Anemia in Vaso-occlusive Painful Normal control values were provided by Crisis without Bacterial Infection 16 healthy adult subjects who had H b A A. T h e reagents used were obtained from NBT Positive the Sigma Chemical Company. T h e Corrected (%) Total method used for the N B T test was a modiSponTemperature Leukocyte fication of that of Feigin and co-workers. 3 (F.) Count taneous Stimulated
610
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WAJIMA
Table 3. Results of NBT Tests during Sickle-cell Anemia in Vaso-occlusive Painful Crisis with Bacterial Infection N B T Positive
(%) Corrected Total Leukocyte Count
Temperature
27,800
104.0
23,000 22,830
Spontaneous
Stimulated
Comment
0
0
Urinary-tract infection
102.4
0
0
Pneumonia
102.0
4
35
Pneumonia
21,050
103.0
0
0
21,000
104.0
3
25
Pneumonia
20,800
102.4
1
20
Pneumonia
19,000
102.2
0
10
Pneumonia
18,000
102.2
6
21
Pneumonia
17,300
104.0
2
20
Pneumonia
16,600
102.2
1
8
Urinary-tract infection
15,300
101.0
0
16
Urinary-tract infection
14,900
101.6
2
30
Pneumonia
13,700
103.6
2
18
Urinary-tract infection
1.61 2.70
18.7 24.74
Table 4. Results of NBT Tests during Sickle-cell Anemia with Bacterial Infection without Vaso-occlusive Painful Crisis NBT Positive (%) Corrected Total Leukocyte Count
Temperature (F.)
Spontaneous
21,800
104.4
0
0
Pneumonia
20,100
103.0
4
35
Pneumonia
17,700
102.0
0
19
Acute pelvic inflammatory disease and urinary-tract infection
17,620
103.2
7
23
Acute pelvic inflammatory disease and urinary-tract infection
17,000
100.6
8
37
Cholecystitis
16,000
100.0
3
35
Leg ulcer with infection
14,800
101.0
2
30
Pneumonia
13,900
103.0
2
18
Urinary-tract infection
11,550
100.6
5
29
Pelvic inflammatory disease
3.44 2.26
25.11 7.65
MEAN
S.D.
Stimulated
Comment
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
MEAN
S.D.
Acute pelvic inflammatory disease and urinary-tract infection
November 1975
NBT TEST IN SICKLE-CELL ANEMIA
not respond to bacterial infection with a positive N B T test result. Sickle-cell anemia in painful crisis showed lower N B T positivity with bacterial infection than without bacterial infection. T h e patients who had bacterial infection with crisis tended to have lower N B T scores than the patients in a steady state. Alterations of the cell surface and metabolism during bacterial infection may be among the factors responsible for decreased reduction of N B T dye. T h e difference between these two groups cannot be explained. Two patients who failed to respond to the N B T test had histories of frequent bacterial pneumonia.
T h e exact mechanism of N B T reduction is unclear. In-vitro stimulation of blood from normal persons without cellular or humoral defect and without defect in neutrophilic leukocyte metabolism will show a marked increase in the percentage of positive neutrophils. 4,5 It is noteworthy that none of the sickle-cell anemia patients we studied had a glucose-6-phosphate dehydrogenase deficiency. Dimitrov and associates 2 reported that sickle-cell anemia patients who had histories of infection had low N B T reduction and other metabolic defects of neutrophilic leukocytes, in contrast to patients without a history of infection. Winkelstein and Drachman 8 reported a marked deficiency of pneumococcal serum-opsonizing activity in sickle-cell anemia. Therefore, reduced N B T test scores may be the result of impaired function of neutrophils and a defective complement system in sickle-cell anemia. Most patients who have sickle-cell anemia, in painful crisis or in a steady Discussion state, have leukocytosis. Fever and leukoFrom this study it is evident that sickle- cytosis are common in the painful crisis cell anemia patients in painful crisis with of sickle-cell anemia and also in bacterial bacterial infection have low baseline N B T infection. It is often difficult to differenpositivity, and have even lower positivity tiate vaso-occlusive painful crisis and after in-vitro stimulation. Even more signifi- bacterial infection with or without crisis cant was a demonstration that some of the in the patient who has sickle-cell anemia. patients who had sickle-cell anemia did During painful crisis, the N B T test has
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
(S.D.) (range 4-18%) and the mean stimulated N B T score was 50±19.16% (range 32-69%). In sickle-cell anemia in the steady state, NBT reduction was 5.75 ± 4.84% (range 0 - 1 4 % in the spontaneous test compared with 32.3 ± 9.52% (range 20-50%) in the stimulated test (Table 1). In vaso-occlusive painful crisis without bacterial infection the N B T score was 6.9 ± 2.97% (range 0-12%) in the spontaneous test, and 39.2 ± 9.38% (range 20-52%) in the stimulated test (Table 2). Thirteen patients in painful crisis with bacterial infection had decreased spontaneous and stimulated N B T scores. T h e unstimulated test score was 1.61 ± 2.70% (range 0-6%) compared with 18.7 ± 24.74% (range 0-41%) in the stimulated test (Table 3). Nine patients with bacterial infection and without painful crisis had a spontaneous reduction of N B T of 3.44 ± 2.26% (range 0-8%) and stimulated reduction of N B T of 25.11 ± 7.65% (range 1-37%) (Table 4). T h e reduction of N B T by neutrophilic leukocytes from sickle-cell anemia patients with bacterial infection either with or without crisis was significantly less in both spontaneous and stimulated tests than that of the normal controls. T h e N B T scores of sickle-cell anemia patients, both in the steady state and in painful crisis, without bacterial infection were slightly higher than those of patients with infections with or without crisis. When a bacterial infection was present the histochemical reduction of N B T dye was decreased.
611
612
WAJIMA
AJ.CP.-VoL
64
limited usefulness in identifying the infectious complication as a precipitating factor. When the NBT test is used in sickle-cell anemia, a negative or low result does not rule out bacterial infection.
News and Notices American Association of Clinical Chemists Publication T h e American Association of Clinical Chemists has published a tabulation of results obtained for clinical chemistry tests performed on normal children. More than 100 determinations are listed, along with the procedures followed, special equipment used, and age variations. Data were obtained from seven major pediatric hospitals in the United States and Canada on children ranging from neonates to adolescents. T h e tabulation is the first in a series planned by The Special Committee on Pediatric Clinical Chemistry. Copies of the special publication, "Normal Values for Pediatric Clinical Chemistry," can be obtained by writing to the American Association of Clinical Chemistry, 1725 K Street N.W., Washington, D.C. 20006, U.S.A. Non-members of the Association should include $2 (U.S.) for each copy.
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
3. Feigin RD, Shackelford PG, Choi SC, et al: Nitroblue tetrazolium dye test as an aid in the differential diagnosis of febrile disorders. J Pediatr 78:376-378, 1971 4. Matula G, Paterson PY: Spontaneous in vitro reduction of nitroblue tetrazolium by neutrophils of adult patients with bacterial infection. N Engl J Med 285:311-316, 1971 Acknowledgment. Dr. L. W. Diggs offered sug- 5. Nauman HN, Diggs LW, Barreras L, et al: Plasma hemoglobin and hemaglobin fracgestions and criticism. tions in sickle cell crisis. Am J Clin Pathol 56:137-147, 1971 References 6. Park BH, Fikrig SM, Smithwhick EH: Infection and nitroblue tetrazolium reduction by 1. Bittner SJ, Kieff E, Windhorst D, et al: The use neutrophils. Lancet 2:532-534, 1968 of the unstimulated nitroblue tetrazolium 7. Park BH: The use and limitations of the nitrotest as a routine screening test for bacterial blue tetrazolium test as a diagnostic aid. J infection in an adult population. Am J Clin Pediatr 78:376-378, 1971 Pathol 60:843-853, 1973 2. Dimitrov NV, Douwes FR, Bartolotta B, et al: 8. Winkelstein JA, Drachman RH: Deficiency of Metabolic activity of polymorphonuclear pneumococcal serum opsonizing activity in leukocytes in sickle cell anemia. Acta sickle-cell disease. N Engl J Med 279:459466, 1968 Haematol 47:283-291, 1972
M.D.
Sickle Cell Center, Department of Medicine, University of Tennessee College of Medicine, Memphis, Tennessee 38163
ABSTRACT
I T IS W E L L K N O W N that patients who have sickle-cell anemia often are abnormally susceptible to bacterial infection, particularly with Pneumococcus, Meningococcus, and Salmonella. T h e neutrophilic leukocyte is one of the important factors in the host's defense mechanism against bacterial invasion. Dimitrov and associates2 reported that neutrophils from patients who had sicklecell anemia and histories of infection possess a metabolic defect that probably interferes with the destruction of material ingested during phagocytosis. Park and colleagues 6 found that normal neutrophilic leukocytes are capable of spontaneously reducing the dye nitroblue tetrazolium (NBT). T h e percentage of
neutrophils reducing the dye in vitro was shown to increase markedly in febrile states and/or leukocytosis induced by bacterial infection, provided the leukocytes were metabolically normal. 3 ' 4,6,7 False-negative results have been reported to occur in N B T tests of sickle-cell anemia patients who have meningococcal meningitis or Salmonella osteomyelitis 4 and sickle-cell crisis.1 However, there has been no study of the reliability of the N B T test in sickle-cell anemia with infection. Sickle-cell anemia patients in painful crisis with and without bacterial infections, and those in a steady state, were examined to evaluate the usefulness of the N B T test.
Received August 22, 1974; received revised manuscript March 24, 1975; accepted for publication March 24, 1975. Supported by USPHS Grant HL15169 and HL07275. Address reprint requests to Dr. Wajima at his present address: Veterans Administration Hospital, 1030 Jefferson Avenue, Memphis, Tennessee 38104.
Blood samples for the N B T test were obtained from 44 patients who had sicklecell anemia (Hb SS). Their ages ranged from 18 to 36 years. Thirteen were in vasoocclusive painful crisis with bacterial infection, nine had bacterial infection without
608
Materials and Methods
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
Wajima, Takeshi: Nitroblue tetrazolium test in patients with sickle-cell anemia. Am J Clin Pathol 64: 608-612, 1975. Forty-four patients who had sickle-cell anemia were examined to evaluate the reliability and usefulness of the nitroblue tetrazolium (NBT) test. T h e patients with sickle-cell anemia in painful crisis with bacterial infection often had low percentages of N B T reduction or negative results. T h e NBT test did not differentiate well between sickle-cell anemia with bacterial infection and without bacterial infection. (Key words: Nitroblue tetrazolium (NBT) test; Sicklecell anemia; Infection.)
November 1975
NBT TEST IN SICKLE-CELL ANEMIA
609
"Spontaneous" NBT Test
19,100 18,150 18,100 17,200 15,400 13,500 13,500 12,950 12,100 11,600
101.2 102.0 101.6 101.0 99.8 99.2 99.6 99.4 100.0 100.8
7 4 12 10 8 0 3 9 10 5 6.8 2.97
42 36 38 49 48 34 20 33 52 40 39.2 9.38
NBT solution, 0.1 ml., was mixed with 0.1 ml. of heparinized blood and incubated for 30 minutes at 37 C. Smears of the mixture were made, air-dried, and stained with Wright's stain. One hundred neutrophils were counted. MEAN S.D. T h e cells containing discrete intracellular, large, irregularly-shaped deposits were considered positive. Results were excubated for 30 minutes at 37 C. NBT pressed as percentages positive after solution, 0.1 ml., was added, and then the counting 100 neutrophils. N B T test was performed as described above. In-vitro Stimulated NBT Test Results Stimulant solution (bacterial extract), For the 16 healthy controls, the mean 0.05 ml., was mixed with 0.05 ml. of heparinized blood and the mixture was in- spontaneous N B T score was 9.12 ± 7.98%
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
Table 1. Results of N B T Tests during painful crisis, ten had vaso-occlusive crisis Steady-state Sickle-cell Anemia without any evidence of infection, and 12 were in a steady state. NBT Positive T h e presence of a bacterial infection was Corrected (%) Total documented in each instance by culture of Sponthe appropriate material (sputum, urine, Leukocyte Temperature (F.) taneous Stimulated Count vaginal discharge, or blood), response to 28* 99.8 2 16,600 antibiotics, and chest x-ray where indi99.2 2 22 15,100 cated. T h e clinical data are summarized in 8 50 14,900 99.2 Tables 1-4. 6 28 14,200 98.6 14 40 99.4 13,800 T h e vaso-occlusive painful crisis of 0 20 13,800 99.0 sickle-cell anemia was defined as an epi4 29 13,200 99.0 44 6 13,160 sode of acute pain, fever, and vascular 99.2 7 42* 13,000 99.6 obstruction produced by sickled erythro24 4 11,900 99.0 cytes that could not be explained in any 11,860 98.8 33 6 other basis. 11,000 28 10 98.6 32.3 M E A N 5.75 T h e steady state was defined as the status S.D. 4.84 9.52 of a sickle-cell anemia patient during the * Leg ulcer--not infected. intervals between febrile, painful crises, when acute symptoms and fever were Table 2. Results of NBT Tests during Sickleabsent, but chronic anemia persisted. 5 cell Anemia in Vaso-occlusive Painful Normal control values were provided by Crisis without Bacterial Infection 16 healthy adult subjects who had H b A A. T h e reagents used were obtained from NBT Positive the Sigma Chemical Company. T h e Corrected (%) Total method used for the N B T test was a modiSponTemperature Leukocyte fication of that of Feigin and co-workers. 3 (F.) Count taneous Stimulated
610
A.J.C.P.—Vol. 64
WAJIMA
Table 3. Results of NBT Tests during Sickle-cell Anemia in Vaso-occlusive Painful Crisis with Bacterial Infection N B T Positive
(%) Corrected Total Leukocyte Count
Temperature
27,800
104.0
23,000 22,830
Spontaneous
Stimulated
Comment
0
0
Urinary-tract infection
102.4
0
0
Pneumonia
102.0
4
35
Pneumonia
21,050
103.0
0
0
21,000
104.0
3
25
Pneumonia
20,800
102.4
1
20
Pneumonia
19,000
102.2
0
10
Pneumonia
18,000
102.2
6
21
Pneumonia
17,300
104.0
2
20
Pneumonia
16,600
102.2
1
8
Urinary-tract infection
15,300
101.0
0
16
Urinary-tract infection
14,900
101.6
2
30
Pneumonia
13,700
103.6
2
18
Urinary-tract infection
1.61 2.70
18.7 24.74
Table 4. Results of NBT Tests during Sickle-cell Anemia with Bacterial Infection without Vaso-occlusive Painful Crisis NBT Positive (%) Corrected Total Leukocyte Count
Temperature (F.)
Spontaneous
21,800
104.4
0
0
Pneumonia
20,100
103.0
4
35
Pneumonia
17,700
102.0
0
19
Acute pelvic inflammatory disease and urinary-tract infection
17,620
103.2
7
23
Acute pelvic inflammatory disease and urinary-tract infection
17,000
100.6
8
37
Cholecystitis
16,000
100.0
3
35
Leg ulcer with infection
14,800
101.0
2
30
Pneumonia
13,900
103.0
2
18
Urinary-tract infection
11,550
100.6
5
29
Pelvic inflammatory disease
3.44 2.26
25.11 7.65
MEAN
S.D.
Stimulated
Comment
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
MEAN
S.D.
Acute pelvic inflammatory disease and urinary-tract infection
November 1975
NBT TEST IN SICKLE-CELL ANEMIA
not respond to bacterial infection with a positive N B T test result. Sickle-cell anemia in painful crisis showed lower N B T positivity with bacterial infection than without bacterial infection. T h e patients who had bacterial infection with crisis tended to have lower N B T scores than the patients in a steady state. Alterations of the cell surface and metabolism during bacterial infection may be among the factors responsible for decreased reduction of N B T dye. T h e difference between these two groups cannot be explained. Two patients who failed to respond to the N B T test had histories of frequent bacterial pneumonia.
T h e exact mechanism of N B T reduction is unclear. In-vitro stimulation of blood from normal persons without cellular or humoral defect and without defect in neutrophilic leukocyte metabolism will show a marked increase in the percentage of positive neutrophils. 4,5 It is noteworthy that none of the sickle-cell anemia patients we studied had a glucose-6-phosphate dehydrogenase deficiency. Dimitrov and associates 2 reported that sickle-cell anemia patients who had histories of infection had low N B T reduction and other metabolic defects of neutrophilic leukocytes, in contrast to patients without a history of infection. Winkelstein and Drachman 8 reported a marked deficiency of pneumococcal serum-opsonizing activity in sickle-cell anemia. Therefore, reduced N B T test scores may be the result of impaired function of neutrophils and a defective complement system in sickle-cell anemia. Most patients who have sickle-cell anemia, in painful crisis or in a steady Discussion state, have leukocytosis. Fever and leukoFrom this study it is evident that sickle- cytosis are common in the painful crisis cell anemia patients in painful crisis with of sickle-cell anemia and also in bacterial bacterial infection have low baseline N B T infection. It is often difficult to differenpositivity, and have even lower positivity tiate vaso-occlusive painful crisis and after in-vitro stimulation. Even more signifi- bacterial infection with or without crisis cant was a demonstration that some of the in the patient who has sickle-cell anemia. patients who had sickle-cell anemia did During painful crisis, the N B T test has
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
(S.D.) (range 4-18%) and the mean stimulated N B T score was 50±19.16% (range 32-69%). In sickle-cell anemia in the steady state, NBT reduction was 5.75 ± 4.84% (range 0 - 1 4 % in the spontaneous test compared with 32.3 ± 9.52% (range 20-50%) in the stimulated test (Table 1). In vaso-occlusive painful crisis without bacterial infection the N B T score was 6.9 ± 2.97% (range 0-12%) in the spontaneous test, and 39.2 ± 9.38% (range 20-52%) in the stimulated test (Table 2). Thirteen patients in painful crisis with bacterial infection had decreased spontaneous and stimulated N B T scores. T h e unstimulated test score was 1.61 ± 2.70% (range 0-6%) compared with 18.7 ± 24.74% (range 0-41%) in the stimulated test (Table 3). Nine patients with bacterial infection and without painful crisis had a spontaneous reduction of N B T of 3.44 ± 2.26% (range 0-8%) and stimulated reduction of N B T of 25.11 ± 7.65% (range 1-37%) (Table 4). T h e reduction of N B T by neutrophilic leukocytes from sickle-cell anemia patients with bacterial infection either with or without crisis was significantly less in both spontaneous and stimulated tests than that of the normal controls. T h e N B T scores of sickle-cell anemia patients, both in the steady state and in painful crisis, without bacterial infection were slightly higher than those of patients with infections with or without crisis. When a bacterial infection was present the histochemical reduction of N B T dye was decreased.
611
612
WAJIMA
AJ.CP.-VoL
64
limited usefulness in identifying the infectious complication as a precipitating factor. When the NBT test is used in sickle-cell anemia, a negative or low result does not rule out bacterial infection.
News and Notices American Association of Clinical Chemists Publication T h e American Association of Clinical Chemists has published a tabulation of results obtained for clinical chemistry tests performed on normal children. More than 100 determinations are listed, along with the procedures followed, special equipment used, and age variations. Data were obtained from seven major pediatric hospitals in the United States and Canada on children ranging from neonates to adolescents. T h e tabulation is the first in a series planned by The Special Committee on Pediatric Clinical Chemistry. Copies of the special publication, "Normal Values for Pediatric Clinical Chemistry," can be obtained by writing to the American Association of Clinical Chemistry, 1725 K Street N.W., Washington, D.C. 20006, U.S.A. Non-members of the Association should include $2 (U.S.) for each copy.
Downloaded from http://ajcp.oxfordjournals.org/ by guest on June 5, 2016
3. Feigin RD, Shackelford PG, Choi SC, et al: Nitroblue tetrazolium dye test as an aid in the differential diagnosis of febrile disorders. J Pediatr 78:376-378, 1971 4. Matula G, Paterson PY: Spontaneous in vitro reduction of nitroblue tetrazolium by neutrophils of adult patients with bacterial infection. N Engl J Med 285:311-316, 1971 Acknowledgment. Dr. L. W. Diggs offered sug- 5. Nauman HN, Diggs LW, Barreras L, et al: Plasma hemoglobin and hemaglobin fracgestions and criticism. tions in sickle cell crisis. Am J Clin Pathol 56:137-147, 1971 References 6. Park BH, Fikrig SM, Smithwhick EH: Infection and nitroblue tetrazolium reduction by 1. Bittner SJ, Kieff E, Windhorst D, et al: The use neutrophils. Lancet 2:532-534, 1968 of the unstimulated nitroblue tetrazolium 7. Park BH: The use and limitations of the nitrotest as a routine screening test for bacterial blue tetrazolium test as a diagnostic aid. J infection in an adult population. Am J Clin Pediatr 78:376-378, 1971 Pathol 60:843-853, 1973 2. Dimitrov NV, Douwes FR, Bartolotta B, et al: 8. Winkelstein JA, Drachman RH: Deficiency of Metabolic activity of polymorphonuclear pneumococcal serum opsonizing activity in leukocytes in sickle cell anemia. Acta sickle-cell disease. N Engl J Med 279:459466, 1968 Haematol 47:283-291, 1972
