<prompt> Answer this question truthfullyWhat are the possible diagnoses that can distinguish Yersinia pestis infection from other conditions?  <response>: <reason> Conditions that also cause lymphadenopathy: Streptococcal or staphylococcal adenitis Staphylococcus aureus, Staphylococcus pyogenes Purulent or inflamed lesion often noted distal to involved nodes ie, pustule, infected traumatic lesion Involved nodes more likely to be fluctuant Associated ascending lymphangitis or cellulitis may be present generally not seen with plagueInfectious mononucleosisTularemia Francisella tularensis Ulcer or pustule often present distal to involved nodes Clinical course rarely as fulminant as in plague Systemic toxicity uncommonCat scratch fever Bartonella henselae History of contact with cats; usually history of cat scratch Indolent clinical course; progresses over weeks Primary lesion at site of scratch often present small papule, vesicle Systemic toxicity not presentMycobacterial infection, including scrofula Mycobacterium tuberculosis and other Mycobacterium species With scrofula, adenitis occurs in cervical region Usually painless Indolent clinical course Infections with species other than M tuberculosis more likely to occur in immunocompromised patientsLymphatic filariasis Tick typhusConditions that also cause intra-abdominal lymphadenopathy: Appendicitis Acute cholecystitis EnterocolitisCondition that also causes inguinal lymphadenopathy: Lymphogranuloma venereum Chlamydia trachomatis Adenitis occurs in the inguinal region History of sexual exposure 10-30 days previously Suppuration, fistula tracts common Although LGV buboes may be somewhat tender, exquisite tenderness usually absent Although patients may appear ill headache, fever, myalgias, systemic toxicity not presentChancroid Haemophilus ducreyi Adenitis occurs in the inguinal region Ulcerative lesion present Systemic symptoms uncommon; toxicity does not occurPrimary genital herpes Herpes lesions present in genital area Adenitis occurs in the inguinal region Although patients may be ill fever, headache, severe systemic toxicity not presentPrimary or secondary syphilis Treponema pallidum Enlarged lymph nodes in the inguinal region Lymph nodes generally painless Chancre may be noted with primary syphilisStrangulated inguinal hernias Evidence of bowel involvementConditions that manifest similarly:Non-specific sepsis syndrome Gram negative sepsis Pneumonic plague should be differentiated from the following diseases:Inhalational anthrax Bacillus anthracis Widened mediastinum and pleural effusions seen on CXR or chest CT Not true pneumonia; minimal sputum production Hemoptysis uncommon if present, suggests diagnosis of plagueTularemia Francisella tularensis Clinical course not as rapid or fulminant as in pneumonic plagueMycoplasmal pneumonia Mycoplasma pneumoniae Rarely as fulminant as pneumonic plaguePneumonia caused by Chlamydia pneumoniae Rarely as fulminant as pneumonic plagueLegionnaires disease Legionella pneumophila or other Legionella species Rarely as fulminant as pneumonic plague Community outbreaks of Legionnaires disease often involve exposure to cooling systems Legionellosis and many other diseases caused by bacterial agents S aureus, S pneumoniae, H influenzae, K pneumoniae, M catarrhalis usually occur in persons with underlying pulmonary or other disease or in the elderlyPsittacosis Chlamydia psittaci Rarely as fulminant as pneumonic plague Result of bird exposureOther bacterial agents eg, Staphyloccocus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Klebsiella pneumoniae, Moraxella catarrhalis Rarely as fulminant as pneumonic plague Usually occur in persons with underlying pulmonary or other disease or in the elderlyInfluenza Influenza generally seasonal October-March in United States or involves history of recent cruise ship travel or travel to tropicsHantavirus Exposure to excrement urine or feces of mice with HantavirusRSV RSV usually occurs in children although may be cause of pneumonia in elderly; tends to be seasonal winterspringCMV CMV usually occurs in immunocompromised patientsQ fever Coxiella burnetii Exposure to infected parturient cats, cattle, sheep, goats Severe pneumonia not prominent featureLeptospirosisHantavirus pulmonary syndromeviral pneumonia 