Snapshot A 52-year-old man presents to the emergency department for fever, chills, and pain in the left foot. His symptoms progessively worsened over the course of a week. Medical history is significant for poorly controlled type II diabetes mellitus. On physical exam, there is tenderness to palpation of the left foot. Laboratory testing is significant for an elevated erythrocyte sedimentation rate and C-reactive protein; as well as, a leukocytosis. A plain radiograph demonstrates periosteal thickening and soft tissue swelling. Introduction Clinical definition inflammation of the bone and bone marrow most commonly due secondarily to infection that can be categorized as acute osteomyelitis more common in children typically symptom onset is within 2 weeks postinfection chronic osteomyelitis more common in adults typically symptoms persists months or years postinfection Epidemiology risk factors diabetes peripheral vascular disease open fracture intravenous drug use catheter use surgery Etiology note that infection can be due to bacteria, fungi, and mycobacteria microbiology Staphylococcus aureus most common cause overall (including pediatric patients) may be seen in sickle cell disease prosthetic joint replacement vertebral involvement focal back pain/tenderness intravenous drug use Neisseria gonorrhoeae rare Staphylococcus epidermidis can also be seen in prosthetic joint involvement Mycobacterium tuberculosis can also be seen in cases of vertebral involvement (Pott disease) Pasteurella multocida seen in cases caused by cat and dog bites Pseudomonas and Candida can also be seen in cases caused by intravenous drug abuse Pathogenesis hematogenous seeding of bone contiguous spread of infection from adjacent structures (e.g., soft tissues and joints) direct inoculation e.g., penetrating trauma and contaminated surgical tools Prognosis mortality has significantly decreased since the use of antibiotics Presentation Symptoms acute osteomyelitis lethargy acute pain in affected site erythema and chronic osteomyelitis chronic pain Physical exam swelling erythema tenderness reduced range of motion bone tenderness ulcers exposed bone may be seen sinus tract pathognomonic for chronic osteomyelitis must perform a neurovascular exam Imaging Radiographs indication preferred initial test in evaluating for osteomyelitis note that it takes 10-14 days postinfection for findings to appear findings periosteal thickening and elevation "Codman triangle" Magnetic resonance imaging indication considered when radiography is unrevealing findigs may reveal bone necrosis, abscess, and sinus tracts Studies Labs ↑ C-reactive protein ↑ erythrocyte sedimentation rate leukocytosis present in acute osteomyelitis unlikely to be found in chronic osteomyelitis Biopsy and culture confirms the diagnosis Differential Septic arthritis Gout Cellulitis Osteosarcoma Treatment Medical empiric antibiotics indication considered the mainstay of treatment eventually tailored to organism after culture sensitivities return Operative debridement indication to remove necrotic tissue Complications Bone necrosis Sepsis Squamous cell carcinoma most common tumor associated with osteomyelitis
QUESTIONS 1 of 5 1 2 3 4 5 Previous Next Lab Values Blood Hematologic Cerebrospinal Sweat, Urine, and BMI Blood, Plasma, Serum Reference Range ALT 8-20 U/L Amylase, serum 25-125 U/L AST 8-20 U/L Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL Calcium, serum (Ca2+) 8.4-10.2 mg/dL Cholesterol, serum Rec: < 200 mg/dL Cortisol, serum 0800 h: 5-23 μg/dL //1600 h: 3-15 μg/dL 2000 h: ≤ 50% of 0800 h Creatine kinase, serum Male: 25-90 U/LFemale: 10-70 U/L Creatinine, serum 0.6-1.2 mg/dL Electrolytes, serum Sodium (Na+) 136-145 mEq/L Chloride (Cl-) 95-105 mEq/L Potassium (K+) 3.5-5.0 mEq/L Bicarbonate (HCO3-) 22-28 mEq/L Magnesium (Mg2+) 1.5-2.0 mEq/L Estriol, total, serum (in pregnancy) 24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL 28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL Ferritin, serum Male: 15-200 ng/mLFemale: 12-150 ng/mL Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL Female: premenopause: 4-30 mIU/mL midcycle peak: 10-90 mIU/mL postmenopause: 40-250 pH 7.35-7.45 PCO2 33-45 mmHg PO2 75-105 mmHg Glucose, serum Fasting: 70-110 mg/dL2-h postprandial:<120 mg/dL Growth hormone - arginine stimulation Fasting: <5 ng/mLProvocative stimuli: > 7ng/mL Immunoglobulins, serum IgA 76-390 mg/dL IgE 0-380 IU/mL IgG 650-1500 mg/dL IgM 40-345 mg/dL Iron 50-170 μg/dL Lactate dehydrogenase, serum 45-90 U/L Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL Female: follicular phase: 5-30 mIU/mL midcycle: 75-150 mIU/mL postmenopause 30-200 mIU/mL Osmolality, serum 275-295 mOsmol/kd H2O Parathyroid hormone, serume, N-terminal 230-630 pg/mL Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L Phosphorus (inorganic), serum 3.0-4.5 mg/dL Prolactin, serum (hPRL) < 20 ng/mL Proteins, serum Total (recumbent) 6.0-7.8 g/dL Albumin 3.5-5.5 g/dL Globulin 2.3-3.5 g/dL Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h Thyroxine (T4), serum 5-12 μg/dL Triglycerides, serum 35-160 mg/dL Triiodothyronine (T3), serum (RIA) 115-190 ng/dL Triiodothyronine (T3) resin uptake 25%-35% Urea nitrogen, serum 7-18 mg/dL Uric acid, serum 3.0-8.2 mg/dL Hematologic Reference Range Bleeding time 2-7 minutes Erythrocyte count Male: 4.3-5.9 million/mm3Female: 3.5-5.5 million mm3 Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/hFemale: 0-20 mm/h Hematocrit Male: 41%-53%Female: 36%-46% Hemoglobin A1c ≤ 6 % Hemoglobin, blood Male: 13.5-17.5 g/dLFemale: 12.0-16.0 g/dL Hemoglobin, plasma 1-4 mg/dL Leukocyte count and differential Leukocyte count 4,500-11,000/mm3 Segmented neutrophils 54%-62% Bands 3%-5% Eosinophils 1%-3% Basophils 0%-0.75% Lymphocytes 25%-33% Monocytes 3%-7% Mean corpuscular hemoglobin 25.4-34.6 pg/cell Mean corpuscular hemoglobin concentration 31%-36% Hb/cell Mean corpuscular volume 80-100 μm3 Partial thromboplastin time (activated) 25-40 seconds Platelet count 150,000-400,000/mm3 Prothrombin time 11-15 seconds Reticulocyte count 0.5%-1.5% of red cells Thrombin time < 2 seconds deviation from control Volume Plasma Male: 25-43 mL/kgFemale: 28-45 mL/kg Red cell Male: 20-36 mL/kgFemale: 19-31 mL/kg Cerebrospinal Fluid Reference Range Cell count 0-5/mm3 Chloride 118-132 mEq/L Gamma globulin 3%-12% total proteins Glucose 40-70 mg/dL Pressure 70-180 mm H2O Proteins, total < 40 mg/dL Sweat Reference Range Chloride 0-35 mmol/L Urine Calcium 100-300 mg/24 h Chloride Varies with intake Creatinine clearance Male: 97-137 mL/minFemale: 88-128 mL/min Estriol, total (in pregnancy) 30 wks 6-18 mg/24 h 35 wks 9-28 mg/24 h 40 wks 13-42 mg/24 h 17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 hFemale: 2.0-8.0 mg/24 h 17-Ketosteroids, total Male: 8-20 mg/24 hFemale: 6-15 mg/24 h Osmolality 50-1400 mOsmol/kg H2O Oxalate 8-40 μg/mL Potassium Varies with diet Proteins, total < 150 mg/24 h Sodium Varies with diet Uric acid Varies with diet Body Mass Index (BMI) Adult: 19-25 kg/m2 Calculator ( ) xy AC 7 8 9 ÷ 4 5 6 × 1 2 3 - 0 . = + Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK You have 100% on this question. Just skip this one for now. Take This Question Anyway (M2.OR.4679) A 55-year-old obese woman is admitted to your floor for chronic fevers. She states she has had fevers of of over 101F as measured on her oral thermometer for the past month. Her vitals are T 100.9 F, HR 95 and regular, RR 16, BP 150/95. On history she states that she has a history of diabetes and is noncompliant with her insulin. She was recently treated for a foot infection with antibiotics, but her fevers have remained. Her last HbA1C was 8.5%. On exam, the patient has no gross deficits, but does admit to pain in her left lower leg and foot. Physical exam reveals a Grade IV ulcer, as displayed in Figure A. She states she has severe pain when bearing weight on her left leg. Otherwise, all extremities have diminished pulses and sensation. There is no erythema in the surrounding area and no areas of fluctuance. Figure B shows AP and lateral radiographs of the patient's left leg. What is the most likely diagnosis? Review Topic | Tested Concept QID: 107280 FIGURES: A B Type & Select Correct Answer 1 Fracture 0% (0/4) 2 Cellulitis 0% (0/4) 3 Abscess 0% (0/4) 4 Osteomyelitis 100% (4/4) 5 Charcot joint 0% (0/4) M2 A Critical Select Answer to see Preferred Response SUBMIT RESPONSE 4 You have 100% on this question. Just skip this one for now. Take This Question Anyway (M3.OR.56) A 66-year-old man presents to his primary care physician complaining of increasing discharge from a lesion on his foot. He noticed it a month ago and states it has been gradually worsening. He has a long history of poorly controlled diabetes with complications including chronic renal failure and peripheral neuropathy. He denies any pain or fevers/chills. Physical exam is notable for the finding in Figure A. Laboratory evaluation is significant for an erythrocyte sedimentation rate of 226 mm/h. Which of the following would be the most accurate imaging test for this patient's condition? Review Topic | Tested Concept QID: 102997 FIGURES: A Type & Select Correct Answer 1 Bone scan 0% (0/3) 2 CT scan 0% (0/3) 3 MRI 67% (2/3) 4 Radiograph 33% (1/3) 5 Ultrasound 0% (0/3) M2 D Tested Select Answer to see Preferred Response SUBMIT RESPONSE 3 You have 100% on this question. Just skip this one for now. Take This Question Anyway (M2.OR.28) A 45-year-old woman with a history of diabetes presents with 1 week of progressively worsening back pain and subjective fevers. Six months ago, she was treated for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, thought to be secondary to an infected diabetic foot ulcer. There was no inciting trauma for the back pain, and she has no urinary incontinence or altered sensation in her back or legs. Her temperature is 101.3°F (38.5°C), blood pressure is 157/99 mm Hg, pulse is 100/min, respirations are 17/min, and oxygen saturation is 98% on room air. She has point tenderness in her back at the L4 level but no apparent swelling or overlying erythema. Her left foot has the findings depicted in Figure A. Which of the following is the most accurate test for this patient's back pain? Review Topic | Tested Concept QID: 104913 FIGURES: A Type & Select Correct Answer 1 Biopsy 0% (0/34) 2 CT 0% (0/34) 3 MRI 9% (3/34) 4 Radiograph 71% (24/34) 5 Ultrasound 18% (6/34) M2 D Tested Select Answer to see Preferred Response SUBMIT RESPONSE 1