NSAIDS;

Do proton pump inhibitors (PPIs) reduce the risk of bleeding from lower gastrointestinal tract?

FA Manian MD, MPH, , , , , , , , , , , , , , Leave a comment

The short answer is “No”!  Although proton pump inhibitors (PPIs) are effective in reducing the risk of upper gastrointestinal bleed (GIB) in high-risk patients, they do not protect against lower GIB. 1 In fact, their use has been associated with an increased risk of small bowel injury related to non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose aspirin.2,3

A 2015 case-control study involving over 1,000 patients hospitalized for GIB found that although concomitant use of PPI in patients on NSAIDs, low-dose aspirin, other antiplatelet agents or anticoagulants was associated with a reduced risk of UGIB, it was not associated with reduced risk of lower GIB.  Interestingly, in this study, PPIs were associated with higher risk of lower GIB which might have been related to confounding factors and not necessarily a direct causal effect.4 Lack of an impact of PPIs on lower GIB among patients on aspirin or NSAIDS has also been supported by others. 5-7

The fact that PPIs don’t seem to reduce the risk of GIB distal to the duodenum should not be surprising given their primary mechanism of action through inhibition of acid production by gastric parietal cells. 8  What is perhaps more intriguing is how they may potentially increase the risk of small intestinal injury while still protecting the gastro-duodenum from NSAID-induced mucosal damage.

In a cool laboratory study involving rats, treatment with a PPI was associated with exacerbation of NSAID-induced intestinal ulceration and bleeding; by itself treatment with PPI was not associated with intestinal mucosa injury.9 Interestingly, in this study, a marked shifts in numbers and types of enteric bacteria with a significant reduction in jejunal Bifidobacteria spp was noted with PPI therapy. Restoration of small intestine Bifididobacteria during treatment with a PPI along with an NSAID prevented intestinal ulceration/bleeding. The investigators concluded that when used along with an NSAID, PPIs may cause small intestinal injury through alteration in the microbiome of the gut.  Fascinating!

Bonus Pearl: Did you know that the 2022 American Gastroenterological Association (AGA) clinical practice update on de-prescribing of PPIs lists several conditions for which acute/short term use of PPIs are NOT indicated, such as isolated lower GI symptomatology, acute nausea and vomiting not believed to be related to GERD/esophagitis, acute undifferentiated abdominal pain, and empiric treatment of laryngopharyngeal symptomatology? 10 

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References

  1. Lue A, Lanas A. Proton pump inhibitor treatment and lower gastrointestinal bleeding: Balancing risks and benefits. World J Gastroenterol 2016;22:10477-10481. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5192259/#:~:text=PPIs%20do%20not%20prevent%20NSAID,and%20the%20risk%20of%20LGB.
  2. Endo H, Sakai E, Taniguchi L, et al. Risk factors for small-bowel mucosal breaks in chronic low-dose aspirin users: data from a prospective multicenter capsule endoscopy registry. Gastrointes Endosc 2014;80:826-34. https://pubmed.ncbi.nlm.nih.gov/24830581/
  3. Washio E, Esaki M, Maehata Y, et al. Proton pump inhibitors increase incidence of nonsteroidal anti-inflammatory drug-induced small bowel injury: A randomized, placebo-controlled trial. Clin Gastroenterol Hepatol 2016;14:809-815. https://pubmed.ncbi.nlm.nih.gov/26538205/
  4. Lanas A, Carrera-Lasfuentes P, Arguedas Y, et al. Risk of upper and lower gastrointestinal bleeding in patients taking nonsteroidal anti-inflammatory drugs, antiplatelet agents, or anticoagulants. Clin Gastroenterol Hepatol 2015;13:906-12. https://pubmed.ncbi.nlm.nih.gov/25460554/
  5. Nagata N, Niikura R, Aoki T, et al. Effect of proton-pump inhibitors on the risk of lower gastrointestinal bleeding associated with NSAIDs, aspirin, clopidogrel, and warfarin. J Gastroenterol 2015;50:1079-1086. https://pubmed.ncbi.nlm.nih.gov/25700638/
  6. Garcia Rodriguez LA, Lanas A, Soriano-Gabarro M, et al. Effect of proton pump inhibitors on risks of upper and lower gastrointestinal bleeding among users of low-dose aspirin: A population-based observational study. J Clin Med 2020;9:928. https://www.mdpi.com/2077-0383/9/4/928
  7. Casado Arroyo R, Polo-Tomas M, Roncales MP, et al. Lower GI bleeding is more common than upper among patients on dual antiplatelet therapy: long-term follow-up of a cohort of a patients commonly using PPI co-therapy. Heart 2012;98:718-723. https://pubmed.ncbi.nlm.nih.gov/22523056/
  8. Engevik AC, Kaji I, Goldenring JR. The physiology of the gastric parietal cell. Physiol Rev 2020;100:573-602. The Physiology of the Gastric Parietal Cell – PMC (nih.gov)
  9. Wallace JL, Syer S, Denou E, et al. Proton pump inhibitors exacerbate NSAID-induced small intestinal injury by inducing dysbiosis. Gastroenterology 2011;141:1314-22. https://www.gastrojournal.org/action/showPdf?pii=S0016-5085%2811%2900926-7
  10. Targownik LE, Fisher DA, Saini SD. AGA clinical practice update on de-prescribing of proton pump inhibitors: expert review. Gastroenterology 2022;162:1334-1342. https://www.gastrojournal.org/article/S0016-5085(21)04083-X/fulltext

Disclosures/Disclaimers: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Do proton pump inhibitors (PPIs) reduce the risk of bleeding from lower gastrointestinal tract?

Are NSAIDS contraindicated in patients with 2019 novel Coronavirus infection (Covid-19)?

FA Manian MD, MPH, , , , , , , , , , , , , , , , , 1 Comment

Despite recent internet reports of the association of non-steroidal anti-inflammatory drugs (NSAIDs) with worsening symptoms among patients with Covid-19 (1), firm clinical evidence to support such claims is currently lacking. However, there are some theoretical reasons why it may still be best to avoid NSAIDs in this condition due to their potential adverse impact on the innate and adaptive immune responses as well as their antipyretic properties (2-9).

 
Blunting of the innate immune response: Certain NSAIDs (eg, ibuprofen, naproxen and celecoxib) inhibit cyclooxygenase enzyme-2 (COX-2) and impair production of several pro-inflammatory cytokines important in fighting infections, such as tumor necrosis factor, interleukin 1 and 6, as well as interferon, an antiviral cytokine (2,6,8). COX-2 has been shown to be important in controlling viral replication in influenza (4). Ibuprofen has been associated with inhibitory effects on a variety of polymorphonuclear functions, including chemotaxis (2).

 
Impact on adaptive immune response: COX-2 inhibition may be associated with impaired neutralizing antibody production (3,4,8). Potential mechanisms include modulation of cytokine expression, nitric-oxide production, and antigen processing/presentation and T lymphocyte activation (3,8).

 
Antipyretic effect: NSAIDs are often given for treatment of fever which is an evolutionary host response to infection. A meta-analysis of animal studies evaluating the impact of antipyretics (including aspirin, NSAIDs, and acetaminophen) in influenza found lower survival in animals treated with antipyretics (9). Longer duration of viral shedding has also been associated with the use of aspirin or acetaminophen in rhinovirus infection (9).

 
Formal epidemiologic and experimental studies are sorely needed to evaluate the safety of NSAIDS in Covid-19.  

 

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References
1. Kolata G. Is ibuprofen really risky for Coronavirus patients? NY Times, March 17, 2020. https://www.nytimes.com/2020/03/17/health/coronavirus-ibuprofen.html
2. Graham NMH, Burrell CJ, Douglas RM, et al. Adverse effects of aspirin, acetaminophen and ibuprofen on immune function, viral shedding, and clinical status in rhinovirus-infected volunteers. J Infect Dis 1990;162:1277-1282. https://academic.oup.com/jid/article/162/6/1277/918184
3. Culbreth MJ, Biryunkov S, Shoe JL, et al. The use of analgesics during vaccination with a live attenuated Yersinia pestis vaccine alters the resulting immune response in mice. Vaccines 2019;7, 205; doi:10.3390/vaccines7040205 https://www.mdpi.com/2076-393X/7/4/205
4. Ramos I, Fernandez-Sesma A. Modulating the innate immune response to influenza A virus:potential therapeutic use of anti-inflammatory drugs. Frontiers in Immunology. July 2015. Volume 6. Article 361. https://www.ncbi.nlm.nih.gov/pubmed/26257731
5. Falup-Pecurariu O, Man SC, Neamtu ML, et al. Effects of prophylactic ibuprofen and paracetamol administration on the immunogenicity and reactogenicity of the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugated vaccine(PHID-CV) co-administered with DTPa-combined vaccines in children:An open-label, randomized, controlled, non-inferiority trial. Human Vaccines & Immunotherapeutics 2017;13: 649-660. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5360152/
6. Housby JN, Cahill CM, Chu B, et al. Non-steroidal anti-inflammatory drugs inhibit the expression of cytokines and induce HSP70 in human monocytes. Cytokine 1999;11:347-58. https://www.ncbi.nlm.nih.gov/pubmed/30186359
7. Agarwal D, Schmader KE, Kossenkov AV, et al. Immune response to influenza vaccination in the elderly is altered by chronic medication use. Immunity & Ageing 2018;15:19. https://www.ncbi.nlm.nih.gov/pubmed/30186359
8. Bancos S, Bernard MP, Topham DJ, et al. Ibuprofen and other widely used non-steroidal anti-inflammatory drugs inhibit antibody production in human cells. Cell Immunol 2009;258:18-28. https://www.ncbi.nlm.nih.gov/pubmed/19345936
9. Eyers S, Weatherall M, Shirtcliffe P, et al. The effect on mortality of antipyretics in the treatment of influenza infection: systematic review and meta-analysis. J R Soc Med 2010;103:403-11. https://www.ncbi.nlm.nih.gov/pubmed/20929891

 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Massachusetts General Hospital, Harvard Catalyst, Harvard University, its affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

Are NSAIDS contraindicated in patients with 2019 novel Coronavirus infection (Covid-19)?

Why is my relatively healthy elderly patient so prone to hyperkalemia?

FA Manian MD, MPH, , , , , , , , , , , , , , , , , , , , , , , Leave a comment

Hyporeninemic hypoaldosteronism (HH)—without impairment of cortisol synthesis— is associated with hyperkalemic (type IV) renal tubular acidosis (RTA) and is not uncommon among older patients despite glomerular filtration rates (GFRs) >20 ml/min, and absence of diabetes mellitus or chronic tubulointerstitial disease (1-7).  

Hyperkalemia due to HH in the elderly should come as no surprise because the renin-angiotensin-aldosterone system (RAAS) function declines with age, reaching its lowest level by age 60. 1-4   In fact, older people have comparatively lower mean levels of plasma renin and aldosterone at baseline and have an impaired ability to mount appropriate responses to RAAS stimuli, such as upright posture, volume depletion, catecholamines, or potassium administration (3-5).

The impaired RAAS capacity in the elderly often becomes more obvious when they are prescribed medications that further suppress RAAS (3). These include angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, calcium-channel blockers, nonsteroidal anti-inflammatory agents and heparin (3,7). 

Drugs that increase aldosterone resistance, including potassium-sparing diuretics (eg, spironolactone, amiloride, triamterene, eplerenone) and certain antibiotics (eg, trimethoprim, pentamidine) may also aggravate hyperkalemia associated with HH (7). 

A variety of mechanisms leading to HH with aging have been proposed. These include impaired conversion of prorenin to renin, prostaglandin deficiency, sympathetic nervous system dysfunction and increased plasma levels of atrial natriuretic factors as found in congestive heart failure (1,7). 

Bonus pearl: Did you know that the first case of “pure hypoaldosteronism” was described in 1957 in a 71 year old non-diabetic patient with hyperkalemia in the setting of congestive heart failure? (8)

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References

  1. Bauer JH. Age-related changes in the renin-aldosterone system. Physiological effects and clinical implications. Drugs & Aging 1993;3:238-45. https://www.ncbi.nlm.nih.gov/pubmed/8324299
  2. Musso CG, Jauregui JR. Renin-angiotensin-aldosterone system and the aging kidney. Expert Rev Endocrinol Metab 2014;9:543-46. https://www.tandfonline.com/doi/full/10.1586/17446651.2014.956723
  3. Yoon HE, Choi BS. The renin-angiotensin system and aging in the kidney. Korean J Intern Med 2014;29:291-95. https://www.researchgate.net/publication/262530577_The_renin-angiotensin_system_and_aging_in_the_kidney
  4. Nadler JL, Lee FO, Hsueh W, et al. Evidence of prostacyclin deficiency in the syndrome of hyporeninemic hypoaldosteronism. N Engl J Med 1986;314:1015-20. https://www.ncbi.nlm.nih.gov/pubmed/3515183
  5. Williams GH. Hyporeninemic hypoaldosteronism. N Engl J Med 1986;314:1041-42. https://www.ncbi.nlm.nih.gov/pubmed/3515186
  6.  Block BL, Bernard S, Schwartzstein RM. Hypo-hypo: a complex metabolic disorder. Ann Am Thorac Soc 2016;13:127-133. https://www.ncbi.nlm.nih.gov/pubmed/26730868
  7. Michelis MF. Hyperkalemia in the elderly. Am J Kid Dis 1990;16:296-99.https://www.ajkd.org/article/S0272-6386(12)80005-9/pdf
  8. Hudson JB, Chobanian AV, Relman AS. Hypoaldosteronism. A clinical study of a patient with an isolated adrenal mineralocorticoid deficiency, resulting in hyperkaliemia and Stokes-Adams attack. N Engl J Med 1957;257:529-36. https://www.ncbi.nlm.nih.gov/pubmed/13464977

 

Why is my relatively healthy elderly patient so prone to hyperkalemia?

My patient just developed a fixed drug reaction from ibuprofen. What is the mechanism of this type of skin reaction?

FA Manian MD, MPH, , , , , , , , Leave a comment

Although its mechanism is not full elucidated, fixed drug eruption (FDE) is thought to result from the drug-induced cytotoxic activation of CD8+ memory T cells.1 ,2

In this context, the culprit medication behaves as a hapten that adheres to basal keratinocytes which in turn results in the recruitment of T cells and inflammation.  However, as the inflammation resolves, CD8+  effector-memory T cells remain in the area in question,  setting the stage for more rapid immunologic reaction when the drug is reintroduced.

Why a systemic drug triggers a reaction only at specific sites in the body is a fascinating question. Prior herpes simplex virus (HSV) infection (eg, on the lips or genitalia) may explain some cases.1 Interestingly, despite the absence of prior herpetic lesions, most patients with FDE are seropositive for HSV. Previously traumatized body sites (e.g. from burns or insect bites) may also create an immune microenvironment conducive to FDE.

The classic presentation of FDE is reappearance of a rash in the genitals, perianal areas, hands, and feet within 30 min to 8 hours of taking the culprit medication.3 Look specifically for NSAIDs, tetracyclines, sulfonamides, and aspirin on the patient’s drug list. 4

References

  1. Shiohara, T. Fixed drug eruption: Pathogenesis and diagnostic tests. Curr Opin Allergy Clin Immunol 2009; 9:316-21. https://www.ncbi.nlm.nih.gov/pubmed/19474709
  2. Butler, DF. Fixed Drug Eruptions. Medscape. http://emedicine.medscape.com/article/1336702-overview#a4. Accessed March 26, 2018.
  3. Korkij W, Soltani K. Fixed drug eruptions: A brief review. Arch Dermatol 1984;120:520. https://www.ncbi.nlm.nih.gov/pubmed/6231004
  4. Oakley, A. Fixed Drug Eruption. https://www.dermnetnz.org/topics/fixed-drug-eruption Accessed March 26, 2018.

 

Contributed by Amir Hossein Ameri, Medical Student, Harvard Medical School

My patient just developed a fixed drug reaction from ibuprofen. What is the mechanism of this type of skin reaction?

What common drugs may exacerbate urinary retention in my patient with spinal cord injury?

FA Manian MD, MPH, , , , , , , , , , , Leave a comment

Anticholinergics (including tricyclic antidepressants-TCAs), selective serotonin reuptake inhibitors (SSRIs), benzodiazepines, opioids, alpha-adrenergics, and non-steroidal anti-inflammatory drugs (NSAIDs) are among the most common agents associated with urinary retention1.  This adverse reaction is particularly observed in patients with pre-existing hypoactive bladder, including those with spinal cord injury (SCI).  Unfortunately, patients with SCI also often require pharmacologic management of neuropathic pain with one or more of these agents (eg, TCAs, opioids, and NSAIDs).

The mechanism of urinary retention may vary depending on the agent. Anticholinergics (eg, TCAs, diphenhydramine) decrease detrusor muscle contraction via blockade of the parasympathetic pathway.1 Opiates may increase the sphincter tone of bladder via sympathetic stimulation, as well as decrease the sensation of bladder fullness by partial inhibition of the parasympathetic nerves that innervate the bladder.2 SSRIs increase external sphincter tone by inhibiting serotonin reuptake.3 Alpha-adrenergics (e.g. ephedrine) can lead to detrusor relaxation and sphincter contraction.3 NSAIDs are thought to inhibit prostaglandin-mediated detrusor contraction.5

Although most patients with SCI have urinary incontinence due to detrusor hyperactivity, some will have urinary retention due to detrusor hyporeflexia.6

Final Fun Fact: Did you know that medications may account for up to 10% of urinary retention episodes? 

 

References

  1. Verhamme KM, Sturkenboom MC, Stricker BH, Bosch R. Drug-induced urinary retention. Drug Saf 2008;31(5):373-88. https://www.ncbi.nlm.nih.gov/pubmed/18422378
  2. Elsamra SE, Ellsworth P. Effects of analgesic and anesthetic medications on lower urinary tract function. Urologic Nursing 2012;32: 60-68. https://www.suna.org/download/education/2014/article320260067.pdf
  3. Thor KB. Serotonin and norepinephrine involvement in efferent pathways to the urethral rhabdosphincter: implications for treating stress urinary incontinence. Urology 2003; 62:3-9. https://www.ncbi.nlm.nih.gov/pubmed/14550831
  4. Glidden RS, DiBona FJ. Urinary retention associated with ephedrine. J Pediatr 1977; 90:1013-4. https://www.ncbi.nlm.nih.gov/pubmed/859049
  5. Verhamme KM, Dieleman JP, Van Wijk MA, et al. Nonsteroidal anti-inflammatory drugs and increased risk of acute urinary retention. Arch Intern Med. 2005;165:1547–1551. https://www.ncbi.nlm.nih.gov/pubmed/16009872
  6. Fowler CJ, O’Malley KJ. Investigation and management of neurogenic bladder dysfunction. J Neurol Neurosurg Psychiatry 2003;74(Suppl IV):iv27–iv31. http://jnnp.bmj.com/content/jnnp/74/suppl_4/iv27.full.pdf

 

Contributed by Alice Choi, Medical Student, Harvard Medical School, Boston, MA.

 

What common drugs may exacerbate urinary retention in my patient with spinal cord injury?

My hospitalized patient has developed hyperkalemia while on heparin prophylaxis. Can heparin really cause hyperkalemia and what is its mechanism?

FA Manian MD, MPH, , , , , , , , Leave a comment

Heparin is one of the most overlooked causes of hyperkalemia in hospitalized patients, occurring in 5-8% of treated patients, including those on thromboprophylaxis1.

The mechanism of heparin-induced hyperkalemia appears to be through suppression of aldosterone synthesis by inhibiting the function of the glomerulosa zone of the adrenal medulla2,3.  Such inhibitory action is usually of no consequence when renal function is normal and potassium excretion is not otherwise impaired.

The risk of heparin-induced hyperkalemia is increased in the elderly, those with preexisting diabetes mellitus or renal insufficiency, as well patients on concomitant use of certain drugs such as spironolactone, ACE inhibitors, NSAIDs, and trimethoprim2. 

Hyperkalemia is usually detected after at least 3-4 days of treatment with subcutaneous heparin, and usually resolves within a few days of  discontinuation of therapy1,2.  Fractionated heparin products such as enoxaparin may also be associated with hyperkalemia2 but the risk appears to be lower1.

Fludrocortisone has been used to normalize serum potassium in patients who  remain on heparin.4

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References

  1. Potti A, Danielson B, Badreddine R, et al. Potassium homeostasis in patients receiving prophylactic enoxaparin therapy. J Thromb Haemost 2004;2:1208-9. http://onlinelibrary.wiley.com/doi/10.1111/j.1538-7836.2004.00791.x/pdf
  2. Thomas CM, Thomas J, Smeeton F, et al. Heparin-induced hyperkalemia. Diabetes Res Clin Pract 2008;80:e7-e8. https://www.ncbi.nlm.nih.gov/pubmed/18343525
  3.  Liu AA, Bui T, Nguyen HV, et al. Subcutaneous unfractionated heparin-induced hyperkalemia in an elderly patient. Australas J Ageing 2009;28:97. https://www.ncbi.nlm.nih.gov/pubmed/19566805
  4. Brown G. Fludrocortisone for heparin-induced hyperkalemia. CJHP 2011;64:463-4. https://www.cjhp-online.ca/index.php/cjhp/article/view/1091/1394

 

My hospitalized patient has developed hyperkalemia while on heparin prophylaxis. Can heparin really cause hyperkalemia and what is its mechanism?

Are GI symptoms such as nausea, vomiting, and diarrhea common in patients with influenza?

FA Manian MD, MPH, , , , , , , Leave a comment

Typically, GI symptoms are more prominent in children with influenza than adults but during the H1N1 epidemic in 2009 (which has subsequently become endemic), up to 26% of hospitalized adults with H1N1 infection had abdominal pain or vomiting and up to 25% had diarrhea (1). 

In fact, H1N1 virus has been isolated from stool of adult hospitalized patients (2,3) and receptors of influenza virus have been identified in human GI epithelial cells, the correlation between GI symptoms and isolation of virus from stool is poorly defined (4).

Interestingly, the mechanism involved in influenza-mediated intestinal injury may have less to do with direct invasion of the intestinal mucosa by the virus and more to do with immune mediated changes  related to alterations in the intestinal microbiota induced by influenza virus infection itself (4,5)! 

Aside from direct or indirect effects of influenza virus on the GI tract, oseltamivir and non-steroidal anti-inflammatory use may also contribute to GI symptoms (4).

 

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References

  1. Writing Committee of the WHO Consultation on Clinical Aspects of Pandemic (H1N1) 2009 influenza. Clinical aspects of pandemic 2009 influenza A (H1N1) virus infection. N Engl J Med 2010;362:1708-19. https://www.ncbi.nlm.nih.gov/pubmed/20445182
  2. Yoo SJ, Moon SJ, Kuak E-Y, et al. Frequent detection of pandemic (H1N1) 2009 virus in stools of hospitalized patients. J Clin Microbiol 2010; 48:2314-2315. https://www.ncbi.nlm.nih.gov/pubmed/20375236
  3. Minodier L, Charrel RN, Ceccaldi PE, et al. Prevalence of gastrointestinal symptoms in patients with influenza, clinical significance, and pathophysiology of human influenza viruses in faecal samples: what do we know? Virol J 2015;12:215. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4676820/
  4. Shu Y, Li CK, Gao R, et al. Avian influenza A(H5N1) viruses can directly infect and replicate in human gut tissues. J Infect Dis 2010;201:1173-7. https://www.ncbi.nlm.nih.gov/pubmed/20210629
  5. Wang J, Li F, Wei H, et al. Respiratory influenza virus infection induces intestinal immune injury via microbiota mediated Th17 cell-dependent inflammation. J Exp Med 2014;211:2397-2410. http://europepmc.org/article/PMC/4235643
Are GI symptoms such as nausea, vomiting, and diarrhea common in patients with influenza?