A 22-year-old male patient, recently incarcerated and now homeless, has received 1 week of clarithromycin for low-grade fever and left upper-lobe pneumonia. He has not improved on antibiotics, with persistent cough productive of purulent sputum and flecks of blood. Repeat chest x-ray suggests a small cavity in the left upper lobe. Which of the following statements is correct?
The patient is high risk for tuberculosis due to his history of incarceration and homelessness. The location of the infiltrate in the upper lobe, as well as the formation of a cavity, further suggests reactivation tuberculosis. Sputum smear and culture for AFB are mandatory. The patient requires respiratory isolation precautions in a negative pressure room, not contact precautions. Anaerobic infection would be in the differential diagnosis of upper lobe infiltrate with cavity formation, but evaluation for tuberculosis is critical because of the risk of person-to-person spread. Single-drug therapy with INH is a good prophylactic regimen but is inappropriate until active TB is excluded. Monotherapy for active TB leads to the rapid development of drug resistance. The pneumococcus rarely causes cavitary pneumonia. Interferon-gamma release assay and tuberculin skin testing with purified protein derivative are used to diagnose latent TB infection, not active TB disease like the patient presented in the vignette.
A 19-year-old male patient presents with a 1-week history of malaise and anorexia followed by fever and sore throat. On physical examination, the throat is inflamed without exudate. There are a few palatal petechiae. Cervical adenopathy is present. The liver span is 12 cm and the spleen is palpable.
Which of the following is the most important initial test combination to order?
This young man presents with classic signs and symptoms of infectious mononucleosis. In a young patient with fever, pharyngitis, lymphadenopathy, and lymphocytosis, the peripheral blood smear should be evaluated for atypical lymphocytes. A heterophile antibody test should be performed. The symptoms described in association with atypical lymphocytes and a positive heterophile test are virtually always caused by Epstein-Barr virus. Neither liver biopsy nor lymph node biopsy is necessary. Workup for toxoplasmosis or cytomegalovirus infection or hepatitis B and C would be considered in heterophile-negative patients. Hepatitis does not occur in the setting of rheumatic fever, and an antistreptolysin O titer is not indicated.
A 30-year-old man presents with right upper quadrant pain. He has been well except for an episode of diarrhea that occurred 4 months ago, just after he returned from a missionary trip to Mexico. He has lost 7 lb. He is not having diarrhea. His blood pressure is 140/70, pulse 80, and temperature 37.5°C (99.5°F). On physical examination there is right upper-quadrant tenderness without rebound. There is some radiation of the pain to the shoulder. The liver is percussed at 14 cm. There is no lower quadrant tenderness. Bowel sounds are normal and active. Which of the following is the most appropriate next step in evaluation of the patient?
The history and physical examination suggest amebic liver abscess. Symptoms usually occur 2 to 5 months after travel to an endemic area. Diarrhea usually occurs first but has usually resolved before the hepatic symptoms develop. The most common presentation for an amebic liver abscess is abdominal pain, usually RUQ. An indirect hemagglutination test is a sensitive assay and will be positive in 90% to 100% of patients. Ultrasound has 75% to 85% sensitivity and shows abscess with well-defined margins. Stool will not show the trophozoite at this stage of the disease process. Blood cultures and broad-spectrum antibiotics would be ordered in cases of pyogenic liver abscess, but this patient’s travel history, the chronicity of his illness, and his lack of clinical toxicity suggest Entamoeba histolytica as the probable cause. Aspiration is not necessary unless rupture of abscess is imminent. Metronidazole remains the drug of choice for amebic liver abscess.
An 80-year-old female patient complains of a 3-day history of a painful rash extending over the right half of her forehead and down to her right eyelid. There are weeping vesicular lesions on physical examination. Which of the following is the most likely diagnosis?
A painful vesicular rash in a dermatomal distribution strongly suggests herpes zoster, although other viral pathogens may also cause vesicles. Herpes zoster may involve the eyelid when the first or second branch of the fifth cranial nerve is affected. Impetigo is a cellulitis caused by group A βhemolytic streptococci. It often involves the face and can occur after an abrasion of the skin. Its distribution is not dermatomal, and while it may cause vesicles, they are usually small and are not weeping fluid. Chickenpox produces vesicles in various stages of development that are diffuse and produce more pruritus than pain. Coxsackievirus can produce a morbilliform vesiculopustular rash, often with a hemorrhagic component and with lesions of the throat, palms, and soles. Herpes simplex virus causes lesions of the lip (herpes labialis) but does not spread in a dermatomal pattern.
A 28-year-old woman presents to her internist with a 2-day history of low-grade fever and lower abdominal pain. She denies nausea, vomiting, or diarrhea. On physical examination, there is temperature of 38.3°C (100.9°F) and bilateral lower quadrant tenderness, without point or rebound tenderness. Bowel sounds are normal. On pelvic examination, an exudate is present and there is tenderness on motion of the cervix. Her white blood cell count is 15,000/µL and urinalysis shows no red or white blood cells. Serum β-hCG is undetectable. Which of the following is the best next step in management?
This patient presents with the clinical picture of pelvic inflammatory disease (PID), including lower quadrant tenderness, cervical motion tenderness, and adnexal tenderness. Fever and mucopurulent discharge are additional evidence for the diagnosis. Treatment requires antibiotic therapy. Ceftriaxone and doxycycline are one recommended regimen that would cover both N gonorrhoeae and C trachomatis. Resistance to fluoroquinolones has emerged in the gonococcus, so previous regimens based on ciprofloxacin or ofloxacin are outdated. The combination of ciprofloxacin and metronidazole would be appropriate if gut organisms were the only pathogens to be covered (for instance, in acute diverticulitis). At times, surgical emergencies may mimic PID and require hospitalization for further observation. CT scan is an excellent diagnostic test for acute appendicitis, but the specific findings of cervical motion tenderness, discharge, and bilateral tenderness all distinguish PID from appendicitis in this patient. Diagnostic laparoscopy is the gold standard for the diagnosis of PID, but this expensive and invasive test is unnecessary in uncomplicated cases. Aztreonam has good gram-negative coverage but does not adequately cover the sexually transmitted pathogens.
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