Noon Report: TTP, Legionnairre's, Vagal Neuropathy
/We had some great noon reports this week, here is a recap on the high yield learning points and resources from each case
The Red Team presented the case of a patient who presented with altered mental status, found to have TTP and newly diagnosed diffuse large cell B lymphoma
Take-away Learning Points:
Microangiopathic hemolytic anemia (MAHA) represents shear damage to erythrocytes as the result of endothelial cell activation or endothelial cell damage. The hallmark finding is schistocytes on peripheral smear. Causes of MAHA include TTP, HUS, DIC, and HELLP
Thrombotic Thrombocytopenic Purpura (TTP) is a clinical diagnosis of MAHA + thrombocytopenia in the absence of another cause of such findings. The classic pentad includes fever, anemia, thrombocytopenia, renal failure, neurologic changes (pneumonic FAT RN)
Prompt diagnosis of TTP is essential since it carries a mortality of 90% without treatment. Treatment for TTP is plasma exchange
References:
Jolly, B et al. “Thrombotic Thrombocytopenic Purpura.” Blood. 2017
The Blue Team presented the case of a patient who presented with high fevers, diarrhea, and abdominal pain found to have Legionnairre’s disease
Take-away Learning Points:
Clinical/lab features suggestive (though no pathopneumonic) of Legionella include high fevers up to 104 degrees, concurrent headache/AMS, concurrent diarrhea, hyponatremia, CRP>100 mg/L, and transaminitis
The urine antigen most commonly used for diagnosis only detects serogroup 1 which makes up 90% of Legionnairre’s disease. Other methods of diagnosis include PCR and culture (gold standard but very difficult)
Treatment requires atypical coverage, most commonly azithromycin or levofloxacin. Other options include doxycycline. No RCT have been done for antibiotic duration. If a patient is immunosuppressed, they are often given a 14 day regimen
References:
Schuetz, P., Haubitz, S., Christ-Crain, M., Albrich, W. C., Zimmerli, W., & Mueller, B. (2013). Hyponatremia and anti-diuretic hormone in Legionnaires’ disease. BMC Infectious Diseases, 13, 585.
Peci A, Winter A-L, Gubbay JB. Evaluation and Comparison of Multiple Test Methods, Including Real-time PCR, for Legionella Detection in Clinical Specimens. Front public Heal. 2016;4:175.
The Green Team presented the case of a patient who presented with dysphagia, dysphonia, and aspiration pneumonia after a recent viral illness, found to have a vagal neuropathy
Take-away Learning Points:
Post-viral vegnal neuropathy is an uncommon entity that has been known to occur after a viral upper respiratory infection. While etiology is ultimately unknown, it is postulated to be due to a viral neuropathy similar to Bell’s palsy etc.
Vagal nerve palsy can present with a range of symptoms though it often presents with unilateral or bilateral vocal cord paresis. Symptoms can include dysphonia, dysphagia, and laryngopharyngeal reflux
Post-viral neuropathies are common but often self-limiting processing thus care is most often supportive
References:
Amin, M et al. “Vagal Neuropathy After Upper Respiratory Infection: A Viral Etiology?” American Journal of Otolaryngology. 2001; 22(4): 251-6.
