500
An 18-month-old girl with chronic malnutrition caused by intestinal malabsorption presents to the emergency department with fever, irritability, and left arm weakness. Vital signs show a temperature of 38.2°C, respiratory rate of 36 breaths/min, heart rate of 138 beats/min, blood pressure of 110/50 mm Hg, and a weight of 9 kg. On physical examination, she is irritable, has a facial droop, and left-sided weakness and tremor.
Laboratory data shows:
White blood cells, 8,500/µL (8.5 x 109/L)
/Hemoglobin, 11 g/dL (110 g/L)
/Platelets, 307 x 103/µL (307 x 109/L)
/Differential, 54% segmented neutrophils, 37% lymphocytes, 8% monocytes, 1% eosinophils
/Cerebrospinal fluid (CSF) results:
White blood cells, 147/µL (4% segmented, 83% lymphocytes)
/Red blood cells, 10/µL
/Glucose, 25 mg/dL (1.4 mmol/L)
/Protein, 179 mg/dL
The purified protein derivative skin test result is 14 mm of swelling. You suspect tuberculous meningitis..........
Of the following, the immune defect that BEST explains this child’s increased susceptibility to this infection is.......
A. decreased phagocytic cell function
B. impaired antibody specific responses
C. increased lymphocyte anergy
D. increased natural killer cell levels
E. upregulation of regulatory T cells
C. increased lymphocyte anergy