Which of these children with hematuria needs admission to the hospital?

-A 10-year-old boy with recent sore throat treated with amoxicillin, tea-colored urine, and normal urine output; UA shows microscopic hematuria and proteinuria; blood tests are normal
-A 12-year-old girl with lower abdominal pain, dysuria, urgency, frequency, and pink urine; UA shows microscopic hematuria, > 50 WBCs/hpf, + leukocyte esterase, + nitrites; urine pregnancy test is negative
-A 6-year-old boy with nausea, vomiting, bloody diarrhea, and decreased urine output; UA shows microscopic hematuria and hyaline casts; blood tests show a high WBC count, low hemoglobin, and low platelets
-An 8-year-old girl with diffuse mild edema, tea-colored urine, and normal urine output; UA shows microscopic hematuria and proteinuria; blood tests show a normal WBC count, hemoglobin, and platelets but low protein