Thanks to Dr. Jeffrey D. Cirillo for his outline and presentation, which was the basis of this post.
The most common lymph node swelling is due to infection (lymphadenitis).
- Groin, armpit, neck, under jaw/ears
- Oncological vs. microbiological
- Acute onset (infection) or gradual onset (cancer)
- Painful (infection) or painless (cancer -usually)
- Resolve in a few weeks (viral, self-limiting)
- Fever, night sweats, weight loss (infection, serious)
- Red, discolored, black/blue (infection, serious)
By KC Panchal – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4360228 - Continually increasing, no other indicator (cancer)
- Lymphadenitis –Common Causes
- Streptococcus, Staphylococcus (local skin)
- Mononucleosis (cervical)
- Tuberculosis (mediastinal, hilaradenopathy)
- Tularemia (regional, cervical)
- Yersinia (cervical, abdominal)
- Salmonella (general)
- Rubella (auricular, posterior cervical, occipital)
- Atypical mycobacterial infections (submandibular)
- Histoplasmosis(mediastinal, hilar)
- Chlamydia (conjunctivitis)
- Toxoplasmosis (general)
- Brucella(cervical, rare)
- Diagnostic Approach
- History (chronic vs. acute, other indicator).
- Blood work (liver, kidney, CBC, differential)
- Lymphocytes, neutrophils (infection, leukemia)
- Monocytes (infection)
- Eosinophils(cancer, parasitic infection)
- Chest X-ray (armpit/neck nodes)
- Platelet count (certain cancers)
- Liver-spleen scan
- Tularemia-F. Tularensis
- Rabbits, summer, arthropods
- Gram negative, coccobacilli, facultative intracellular pathogen, survives in phagocytes
- Tularemia I S/S-regional LAD with ulceration 3-5 days, painless rash
- Tularemia II S/S-infection of spleen, liver, bone, lung, granulomas
- Dx-poorly staining, four-fold increase in titers, persistent Ab, ELISA and Cx positive
- Tx-aminoglycosides
- Prevention-limited exposure to rabbits, cook meat well, live attenuated vaccine
- Bubonic Plague-Yerninia Pestis
- Rats, fleas, human to human (droplets)
- Gram negative rod, facultative intracellular, anaerobe, capsulated
- Interaction with host cells via surface adhesins
- S/S-LAD with buboes, painful (2-6 days after flea bite), fever, confusion, back and limb pain
- Dx-blood cx, low level bacteremia, bubo aspirate, sputum (pneumonic), direct fluorescent microscopy, serology, blood agar cx
- Tx-tetracycline or streptomycin, gentamicin/doxy/cipro
- Prevention-vaccine, rodent control, isolation/quarantine
- Brucellosis-Brucella spp.
- Livestock, humans are accidental hosts, ingestion (milk), contact/inhalation
- Gram negative bacilli
- Spreads via lymph, disseminated form causes bacteremia (RES), phagocytosis (granulomas)
- S/S-FUO days to months after exposure (cyclical), malaise, aches, liver dysfunction, granulomas, LAD, osteomyelitis, endocarditis
- Chronic S/S-(one year of illness) fatigue, aches and pains, depression, anxiety, occasional fever
- Dx-Cx (blood or tissue), titers >1:160 is presumptive
- Tx-Doxy and rifampin 6-12 weeks
- Prevention-cattle vaccination, pasteurization of milk, vaccine high risk population
- Chlamydia-C. Trachomatis
- STI/STD, can also cause cervicitis, urethritis, trachoma, conjunctivitis
- Gram negative cocci/oval, obligate intracellular pathogen
- S/S-(lymphogranuloma), first stage-small painless vesicular lesion, fever, headache, and myalgia; second stage-LAD, fever, headache, myalgia, buboes, proctitis, ulcers or elephantiasis
- Dx-Cytology and Cx-iodine staining inclusions, ELISA (LPS), NAT
- Tx-tetracycline, erythromycin, sulfonamides
- Prevention-safe sex habits, treat partners too
- Toxoplasmosis-Toxoplasma gondii
- Domestic cat, humans accidental hosts
- Obligate intracellular parasite
- ⅓ risk of fetal infection with primary maternal infection in pregnancy, death higher in 1st trimester, more infections in 3rd trimester
- Fetus/newborn infections-70-90% are asymptomatic at birth
- Classic triad of symptoms: Chorioretinitis, Hydrocephalus, Intracranial calcifications
- S/S include fever, rash, hepatosplenomegaly, microcephaly, seizures, jaundice, thrombocytopenia, lymphadenopathy
- Initially asymptomatic infants are still at high risk of developing abnormalities, especially chorioretinitis
- Dx-maternal IgG testing indicates past infection, cx-placenta umbilical cord, infant serum, newborn serologies with IgM/IgA
- Tx-adults-sulfadiazine and pyrimethamine plus leucovorin; pregnant women-spiramycin; fetus dx-treat mother spiramycin, pyrimethamine, and sulfadiazine, leucovorin rescue for pyrimethamine; symptomatic newborns-pyrimethamine, leucovorin, and sulfadiazine for 12 months; asymptomatic newborns-same as symptomatic newborns, tx one month
- Prevention-cook meat completely, freezing meat, washing hands/utensils/dishes contact raw meat; environment don’t drink untreated water, keep away from soil used by cats, wear gloves when changing litter box, keep cats indoors, don’t get a new cat or handle unknown cats while pregnant