FEVER
Definition: T>38.5; T>38 (neutropenic pts); T>39 usually an infectious etiology
Fever of unknown origin (FUO): T>38.3 for >3 weeks and after 1 week of inpatient diagnostic workup/3 outpatient visits
Etiologies:
ž Infection (bacterial, viral, fungal, parasitic)
ž Connective Tissue Disease
ž Malignancy (leukemia, lymphoma, renal cell carcinoma, metastatic disease)
ž Miscellaneous: (DVT/PE, Medications, Drug withdrawal, hyperthyroidism)
Diagnostic Workup:
History
ž Travel, sick contacts, tuberculosis history/contacts, IDS risk factors, pets, occupation, medications, trauma, environmental contacts
ž Localizing features: HA, vomiting, diarrhea, cough, hemoptysis, skin rash, joint/bone pains, confusion, sore throat
Physical Exam
ž Rash, lymphadenopathy, murmurs, hepatosplenomegaly, joint exam, pelvic exam (women with abdominal pain)
Laboratory
ž FBP with differential; peripheral smear
o Neutrophilia: bacterial (sepsis, focal infection, deep-seated abscess); amoebic abscess
o Lymphocytosis: Mono, whooping cough, leukemia
o Eosinophilia: parasitic (schisto)
o Normal platelets: viral infections, typhoid, richettsial
o Thrombocytopenia: Malaria, Dengue, IDS
o Pancytopenia: viral, malignancy, autoimmune disease, drugs
o Neutropenia: leukemia
ž Blood Cultures ( 3sets sequentially for endocarditis)
ž BUN/Cr
ž Urinalysis, urine culture
ž Rapid Test
ž MPS
ž Sputum cultures with AFB (pts with cough)
ž Fungal Cultures (IDS/immunocompromised pts)
ž Stool studies (diarrhea)
ž LFTs
ž ESR
ž ANA/RF
ž Fluid analysis (pleural, peritoneal, csf)
ž Bone marrow biopsy
Imaging:
ž CXR
ž Echocardiogram (new murmurs)
ž Abdominal ultrasound (Abdominal pain)
ž Joint xrays
ž Arthrocentesis (joint effusions)
Treatment
ž Antipyretic
ž Cooling blankets for T>39
ž Empiric antibiotics for hemodynamically unstable patients in whom infection is the primary concern and in neutropenic/asplenic patients.
Case 1
55yoM with h/o HTN presents to H2 with 4 weeks of intermittent low-grade fevers to 38. He mainly notes fatigue, malaise and intermittent abdominal pain. Denies cough, chest pain, diarrhea, dyspnea, dysuria, back pain, joint pains. Review of systems also positive for anorexia/weight loss/occasional night sweats.
On evaluation, patient is a thin male with pallor. T 36.7, HR 99, BP 100/50, RR 20 96% oxygenation at room air. Exam notable for bilateral cervical 1cm lymphadenopathy, clear lungs, normal heart, mild upper abdominal tenderness to palpation, +hepatosplenomegaly. No LE edema/no rash.
1. What is your differential diagnosis?
a. The differential for this patient could be quite broad, especially in Tanzania. Differential definitely includes Tb, Malaria, and also malignancy. Parasitic infection could also be present. Endocarditis can present like this as well. IDS status should be considered.
2. What further investigations would you like to do?
a. Blood Cultures, FBP, LFTs are all appropriate initially. Could also perform a US, Hepatits Panel, and consider lymph node Biopsy.
3. How will you treat this patient?
a. Given this patient’s hemodynamic stability, it would be best to hold off on therapy until a diagnosis is made.
Case 2
31yoF with no pmh presents to clinic with 1 week history of nightly fevers to 39.3, chills/rigors and malaise. Patient states she had diarrhea, abdominal pain and myalgias two weeks prior but is now constipated. On ROS, notes occasional HA. Denies cough, abdominal pain/distension, melena, urinary sx,
On evaluation, T 37, HR 90, BP 110/70, RR 15, 99% oxygenation at room. Pt looks ill with pallor. She is laying on stretcher and is alert and oriented x3. Exam notable for dry mucus membranes, sclera anicteric, slightly distended tender abdomen with no organomegaly, normal cardiac and lung exam, no skin rash, no neck stiffness, no LE edema.
1. What is your differential diagnosis? What is the likely diagnosis?
2. What further investigations would you like to do?
3. How would your differential change if the patient had vaginal discharge?
