What are your differential diagnoses (list at least three)?

Analyze this case as you would a client in a clinical setting. You may use your class texts, your pathophysiology text, peer reviewed-journals, and any other reputable sources necessary to help you plan care for this client.
Read the following case study:
Chief Complaint: 11-year-old female presents to pediatric urgent care clinic with fever and left knee pain.
HPI: Patient was in her usual state of health until 6 weeks ago when she began to have intermittent low-grade fevers and joint swelling of her left knee. She does not remember any trauma to the leg and has not had any intercurrent viral illnesses. When asked about the quality of the pain, she reports it as “dull,” constant, limited to her knee, and hurting more at night. It is so uncomfortable that she has been limping for the last 2 days. Her only other symptoms include feeling tired and a slight loss of appetite. She denies any recent trips into the woods and is not sexually active.
Past Medical History: none
Medications: none
Allergies: none
Family History: Mother has systemic lupus erythematosus (SLE). No oncologic disorders.
Social History: Lives at home with mother and father; attends the fifth grade.
Vital Signs: Temp 38 C (100.5F), BP 105/72, HR 79, RR28
Physical Exam:
General: awake alert and oriented x3
HEENT: normal
Neck: positive lymphadenopathy (bilateral anterior cervical)
Abdomen: positive hepatosplenomegaly
Extremities: left leg — swelling of the knee joint, no erythema, but slightly warm. Decreased range of motion and minimal pain on palpation
Remainder of exam normal
Post a response to the following by 11:59PM (EST) on Thursday:
What are pertinent positives on the physical exam and HPI?
What diagnostic tests do you want to perform (provide rationale)?
What are your differential diagnoses (list at least three)?
What psychosocial or cultural aspects are important to this case?