A 74-year-old man is hospitalized with acute urinary retention complicated by urosepsis. He has a urinary catheter placed and is started on intravenous antibiotics. The patient requires endotracheal intubation and mechanical ventilation for 24 hours but is extubated successfully on the second hospitalization day. On the third day of hospitalization, he develops fever and right jaw pain. Physical examination shows firm swelling of the preauricular area on the right side extending to the angle of the mandible. Which of the following serum markers is most helpful for confirming the diagnosis?

Question

A 74-year-old man is hospitalized with acute urinary retention complicated by urosepsis.  He has a urinary catheter placed and is started on intravenous antibiotics.  The patient requires endotracheal intubation and mechanical ventilation for 24 hours but is extubated successfully on the second hospitalization day.  On the third day of hospitalization, he develops fever and right jaw pain.  Physical examination shows firm swelling of the preauricular area on the right side extending to the angle of the mandible.  Which of the following serum markers is most helpful for confirming the diagnosis?

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11ec160b_399a_a4ff_9249_03e6ee734104_MD0001_00 This patient's presentation suggests parotitis, an acute viral or bacterial infection of the parotid gland. Acute bacterial suppurative parotitis can be due to Staphylococcus aureus (most common) or mixed oral aerobes/anaerobes. Risk factors include dehydration, intubation (elderly postoperative patients), medications that decrease salivary flow (eg, anticholinergics), salivary flow obstruction (eg, salivary calculi, oral cavitary neoplasm), or recent intense teeth cleaning. Suppurative parotitis usually presents with acute onset of firm and erythematous pre/postauricular swelling that extends to the mandible. Patients can also develop trismus, dysphagia, and systemic findings (eg, fever, chills). The diagnosis can be confirmed by imaging (eg, ultrasound, CT) showing parotid duct inflammation, obstruction by a stone, or sometimes abscess. As the parotid gland secretes amylase, suppurative parotitis can present with elevated serum amylase. However, affected patients have normal serum lipase levels without clinical evidence of pancreatitis (Choice D). (Choice A) Alkaline phosphatase is an enzyme that hydrolyzes and removes phosphate from other compounds (eg, proteins, enzymes). It is mainly found in the bone, liver, bile ducts, and placenta. Alkaline phosphatase can be elevated in biliary conditions, bone disease (eg, osteomalacia), and leukemia/lymphoma. However, it is usually not affected by parotitis. (Choice C) Gamma-glutamyl transpeptidase (GGT) helps convert glutathione to glutamate. It can be found in many organs, including the liver. GGT elevation suggests that alkaline phosphatase elevation is due to liver (not bone) pathology. (Choice E) Parathyroid hormone (PTH) is secreted by the chief cells of the parathyroid gland and increases serum calcium to maintain calcium homeostasis. PTH has effects on the kidney and bone but is not elevated with parotitis. Educational objective: Acute bacterial parotitis occurs more commonly in elderly postoperative patients who are intubated or dehydrated. Staphylococcus aureus is the most common bacterial etiology. Diagnosis can be confirmed by imaging and an elevated serum amylase level (with a normal serum lipase level and no evidence of pancreatitis). __________ References: Acute bacterial suppurative parotitis: microbiology and management. (http://www.ncbi.nlm.nih.gov/pubmed/12544218) Acute postsurgical suppurative parotitis: current prevalence at Hospital das Clínicas, São Paulo University Medical School. (http://www.ncbi.nlm.nih.gov/pubmed/18949350)

A 74-Year-Old Man Is Hospitalized with Acute Urinary Retention Complicated