The weight of the evidence to date suggests that immunosuppressive therapy, including steroids, other oral immunosuppressants and anti-tumor-necrosis factor (TNF) agents, may negatively impact IGRA results.1
In some ways the finding of false-negative IGRA in the setting of immunosuppression is intuitive since many immunosuppressive agents are potent inhibitors of T cells and interferon-gamma response. 1,2 Despite this, the initial reports have been somewhat conflicting which makes a 2016 meta-analysis of the effect of immunosuppressive therapy on IGRA results in patient with autoimmune diseases (eg, rheumatoid arthritis, lupus, inflammatory bowel disease) particularly timely. 1
This meta-analysis found a significantly lower positive IGRA results among patients on immunosuppressive therapy ( O.R. 0.66, 95% C.I. 0.53-0.83). Breakdown by IGRA test showed a significant association between QuantiFERON-TB Gold In-Tube and lower positive results and a trend toward the same with T-SPOT though the latter did not reach statistical significance with fewer evaluable studies (O.R. 0.81, 95% C.I 0.6-1.1). Breakdown by type of immunosuppressant showed significantly negative impact of corticossteroids, other oral immunosuppressants, and anti-TNF agents for all. Some studies have reported daily steroid doses as low as 7.5 mg-10 mg may adversely impact T-cell responsiveness in IGRA. 3,4
So, whenever possible, testing for latent TB should be performed before immunosuppressants are initiated.
Bonus Pearl: Did you know that an estimated one-third of the world’s population may have latent TB?
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- Wong SH, Gao Q, Tsoi KKF, et al. Effect of immunosuppressive therapy on interferon gamma release assay for latent tuberculosis screening in patients with autoimmune diseases: a systematic review and meta-analysis. Thorax 2016;71:64-72. https://thorax.bmj.com/content/thoraxjnl/71/1/64.full.pdf
- Sester U, Wilkens H, van Bentum K, et al. Impaired detection of Mycobacterium tuberculosis immunity in patents using high levels of immunosuppressive drugs. Eur Respir J 2009;34:702-10. https://erj.ersjournals.com/content/34/3/702
- Kleinert S, Kurzai O, Elias J, et al. Comparison of two interferon-gamma release assays and tuberculin skin test for detecting latent tuberculosis in patients with immune-mediated inflammatory diseases. Ann Rheum Dis 2010;69:782-4. https://ard.bmj.com/content/69/4/782
- Ponce de Leon D, Acevedo-Vasquez E, Alvizuri S, et al. Comparison of an interferon-gamma assay with tuberculin skin testing for detection of tuberculosis (TB) infection in patients with rheumatoid arthritis in a TB-endemic population. J Rheumatol 2008;35:776-81. https://www.ncbi.nlm.nih.gov/pubmed/18398944
There are at least 2 reasons for considering pneumococcal vaccination in hospitalized patients with ulcerative colitis flare.
First, these patients are often on immunosuppressants (eg, glucocorticoids) or biological agents (eg, infliximab) that qualifies them for both 13-valent conjugate (PCV13) and 23-valent polysaccharide (PPSV23) pneumococcal vaccines under the Advisory Committee on Immunization Practices (ACIP) Guidelines’ “Immunocompromised persons” risk group.1-4
Another reason is the possibility of UC patients having coexisting hyposplenism, a major risk factor for pneumococcal disease. Although this association has been described several times in the literature since 1970s, it is relatively less well known. In a study of patients with UC, hyposplenism (either by the presence of Howell-Jolly bodies in the peripheral blood smear or prolongation of clearance from blood of injected radioactively labelled heat-damaged red blood cells) was found in over one-third with some developing life-threatening septicemia in the early postcolectomy period.5
Another study found the majority of patients with UC having slow clearance of heat damaged RBCs despite absence of Howell-Jolly bodies in the peripheral smear.6 Fulminant and fatal pneumococcal sepsis has also been reported in patients with UC.7
Although the immunological response to pneumococcal vaccination may be lower among immunosuppressed patients in general, including those with UC, it should still be administered to this population given its potential benefit in reducing the risk of serious pneumococcal disease. 2,3
- CDC. Intervals between PCV13 and PSV23 vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR 2015;64:944-47. https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6434a4.htm
- Carrera E, Manzano r, Garrido. Efficacy of the vaccination in inflammatory bowel disease. World J Gastroenterol 2013;19:1349-53. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3602493/
- Reich J, Wasan S, Farraye FA. Vaccinating patients with inflammatory bowel disease. Gastroenterol Hepatol 2016;12:540-46. http://www.gastroenterologyandhepatology.net/archives/september-2016/vaccinating-patients-with-inflammatory-bowel-disease/
- Chaudrey K, Salvaggio M, Ahmed A, et al. Updates in vaccination: recommendations for adult inflammatory bowel disease patients. World J Gastroenterol 2015;21:3184-96. https://www.ncbi.nlm.nih.gov/pubmed/25805924
- Ryan FP, Smart RC, Holdworth CD, et al. Hyposplenism in inflammatory bowel disease. Gut 1978;19:50-55. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1411782/
- Jewell DP, Berney JJ, Pettit JE. Splenic phagocytic function in patients with inflammatory bowel disease. Pathology 1981;13:717-23. https://www.ncbi.nlm.nih.gov/pubmed/7335378
- Van der Hoeven JG, de Koning J, Masclee AM et al. Fatal pneumococcal septic shock in a patient with ulcerative colitis. Clin Infec Dis 1996;22:860-1. https://www.ncbi.nlm.nih.gov/pubmed/8722951
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Yes, enteric pathogens such as Salmonella can predispose patients to inflammatory bowel disease (IBD) through several potential mechanisms: 1
- Causing permanent changes in the intestinal microbiota
- Altering the epithelial barrier in the gut
- Altering the interaction between the body’s immune system and the intestines
More specifically, Salmonella utilizes oxidized endogenous sulfur compounds released during acute intestinal inflammation to outgrow the fermentative microbiota of the colon.2 In addition, the neutrophil response to Salmonella infection can alter the constituent microbiome.3 Salmonella also modifies the tight junctions in the intestinal epithelium as it invades, thus activating the immune system (particularly toll-like-receptors), and creating a pro-inflammatory state with structural loss of the intestinal mucosa. 4 Lastly, Salmonella promotes cytokine release and neutrophil migration through pathogen recognition receptors, leaving the intestine in a pro-inflammatory state even following resolution of the infection. 1
Keep in mind that initial Salmonella infection may also mimic IBD, as it causes diffuse lesions in the colon similar to ulcerative colitis, and may cause ileitis in some patients. Stool cultures and biopsies of the colonic mucosa should help differentiate IBD from Salmonella infection. 5
- Schultz BM, Paduro CA, Salazar GA, et al. A potential role of Salmonella infection in the onset of inflammatory bowel diseases. Front Immunol 2017;8:191. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5329042/pdf/fimmu-08-00191.pdf
- Winter SE, Baumler AJ. A breathtaking feat: to compete with the gut microbiota, Salmonella drives its host to provide a respiratory electron acceptor. Gut Microbes 2011;2:58-60. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3225798/pdf/gmic0201_0058.pdf
- Gill N, Ferreira RB, Antunes LC, et al. Neutrophil elastase alters the murine gut microbiota resulting in enhanced Salmonella colonization. PLoS ONE 2012;7:e49646. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0049646
- Bueno SM, Riquelme S, Riedel CA, et al. Mechanisms used by virulent Salmonella to impair dendritic cell function and evade adaptive immunity. Immunology 2012;137:28-36. https://www.ncbi.nlm.nih.gov/pubmed/22703384
- De Hertogh G, Geboes K. Crohn’s disease and infections: a complex relationship. MedGenMed 2004;6:14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1435589
Contributed by Yasmin Islam MD, Mass General Hospital, Boston, MA.
Yes! Although a common cause of colitis, an increasing number of reports in the literature suggest C. difficile can cause enteritis as well.1 Antibiotic use is a major risk factor in most reports, with nearly one-half of the cases reported in patients with inflammatory bowel disease, many post-colectomy. 1-3
Mortality of C. difficile enteritis based on the first 83 cases in the literature appears to be 23%,1 but as high as 60%-83% depending on the report!2 Its diagnosis post-colectomy requires a high index of suspicion, as patients may not complain of “diarrhea” with chronically loose stools in the ileostomy bag. Be particularly on the lookout for C. difficile enteritis in these patients when there is increased stool output, fever, hypotension, and/or leukocytosis2, and when in doubt, send a stool specimen from the ileostomy bag for C. difficile testing.
Although the pathophysiology of C. difficile enteritis is not fully understood, few observations are particularly intriguing:
- Small bowel mucosa may be colonized by C. difficile in about 3% of the population, potentially serving as a reservoir.2
- Patients with ileostomy may develop a metaplasia of the terminal end mimicking colonic environment.4
- Exposure of rabbit ileum to C. difficile toxin A also causes significant epithelial necrosis with destruction of villi and neutrophil infiltration.5
- Dineen SP, Bailey SH, Pham TH, et al. Clostridium difficile enteritis: a report of two cases and systematic literature review. World J Gastrointest Surg 2013;5:37-42. https://www.wjgnet.com/1948-9366/full/v5/i3/37.htm
- Boland E, Thompson JS. Fulminant Clostridium difficile enteritis after proctocolectomy and ileal pouch-anal anastomosis. Gastroenterology Research and Practice 2008; 2008: Article ID 985658. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2633454/pdf/GRP2008-985658.pdf
- Freiler JF, Durning SJ, Ender PT. Clostridium difficile small bowel enteritis occurring after total colectomy. Clin Infect Dis 2001;33:1429-31. https://pdfs.semanticscholar.org/333b/d84978cfc4ac8fd21a15bc8fd26ff3160387.pdf
- Apel R, Cohen Z, Andrews CW, et al. Prospective evaluation of early morphological changes in pelvic ileal pouches. Gastroenterology 1994;107:435-43. http://www.gastrojournal.org/article/0016-5085(94)90169-4/pdf
- Triadafilopoulos G, Pothoulakis C, Obrien MJ, et al. Differential effects of Clostridium difficile toxins A and B on rabbit ileum. Gastroenterology 1987;93:273-279. https://www.ncbi.nlm.nih.gov/pubmed/3596162
Spontaneous coronary artery dissection (SCAD) is defined as the separation of the walls of the coronary artery.1 It is thought that hemorrhage into the false lumen can result in compression of the true lumen, leading to ischemia. Although its exact incidence is unknown, SCAD has been estimated to account for up to 35% of myocardial infarctions in women younger than 50 y of age.2-3
SCAD is often associated with acute chest pain with presentations ranging from acute coronary syndrome (ACS) to sudden cardiac death.1,4 Diagnosis is typically accomplished with coronary angiography and, increasingly, newer modalities such as optical coherence tomography, intravascular ultrasound, and cardiac CT angiography.1
Clinical features that should raise suspicion of SCAD are shown (Table)5. Among many risk factors, myocardial infarction in younger women and the absence of traditional cardiovascular risk factors or lack of typical atherosclerotic lesions in coronary arteries should be potential flags for the possibility of SCAD.
Although the optimal management of SCAD is unclear, conservative therapy with aspirin, clopidogel and beta-blockers has often been recommended5 . Percutaneous coronary intervention (PCI) carries a risk of worsening the dissection or causing additional dissections in such patients1. Revascularization is often reserved for those with hemodynamic instability, persistent ischemia, sustained ventricular tachycardia or fibrillation, or left main dissection.1,5
Table. Clinical features that raise suspicion of SCAD5 ______________________________________________________________________________________________________________
Myocardial infarction in young women (especially age ≤ 50 y)
Absence of traditional cardiovascular risk factors
Little or no evidence of typical atherosclerotic lesions in coronary arteries
History of fibromuscular dysplasia
History of relevant connective tissue disorder (eg, Marfan’s syndrome, Ehler Danlos syndrome)
History of relevant systemic inflammation (incl. SLE, IBD, sarcoidosis, polyarteritis nodosa)
Precipitating stress events caused by emotional or intense physical factors ______________________________________________________________________________________________________________
SLE: Systemic lupus erythematosus; IBD: Inflammatory bowel disease (eg, Crohn’s, ulcerative colitis).
- Saw J, Mancini GB, Humphries KH. Contemporary Review on Spontaneous Coronary Artery Dissection. J Am Coll Cardiol 2016;68:297-312.
- Rashid HN, Wong DT, Wijesekera H, et al. Incidence and characterisation of spontaneous coronary artery dissection as a cause of acute coronary syndrome – a single-centre Australian experience. Int J Cardiol 2016;202:336-8.
- Nakashima T, Noguchi T, Haruta S, et al. Prognostic impact of spontaneous coronary artery dissection in young female patients with acute myocardial infarction: a report from the Angina Pectoris-Myocardial Infarction Multicenter Investigators in Japan. Int J Cardiol 2016;207:341-8.
- Lettieri C, Zavalloni D, Rossini R, et al. Management and long-term prognosis of spontaneous coronary artery dissection. Am J Cardiol 2015;116:66-73.
- Yip A, Saw J. Spontaneous coronary artery dissection-A review. Cardiovasc Diagn Ther 2015;5:37-48. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4329168/pdf/cdt-05-01-037.pdf
Contributed by Mahesh Vidula, MD, Mass General Hospital, Boston, MA.
Howell-Jolly bodies (HJBs, Figure) are often indicative of asplenia (either post-splenectomy or congenital absence) or hyposplenism associated with a variety of conditions, including sickle cell disease, autoimmune disorders, celiac disease, inflammatory bowel disease (particularly ulcerative colitis), HIV, cirrhosis, primary pulmonary hypertension, splenic irradiation, amyloidosis, sarcoidosis, bone marrow transplantation, and high-dose corticosteroid therapy1-4.
Patients with pneumonia and HJBs on peripheral smear may be hyposplenic and at risk of potentially serious infections, predominantly caused by encapsulated bacteria eg, Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis3. Such patients should be immunized against these organisms, including sequential receipt of both conjugated and polysaccharide pneumococcal vaccines3,5.
HJBs are nuclear remnants in circulating mature red blood cells which are usually pitted by the spleen under normal physiological conditions.
Final Fun Pearl: Did you know that HJBs were named after Henry Howell, an American physiologist who pioneered the use of heparin as an anti-coagulant and Justin Jolly, a French hematologist who was among the first to film mitotic activity in cells?
Figure. Howell-Jolly body in an RBC. Photo courtesy of Michael S. Abers, MD
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- Di Sabatino, A, Carsetti R, Corazza G. Post-splenectomy and hyposplenic states. Lancet 2011;378:86–97. https://www.ncbi.nlm.nih.gov/pubmed/21474172
- Brousse, V, Buffet P, Rees D. The spleen and sickle cell disease: the sick(led) spleen. Br J Haematol 2014;166: 165–176. https://www.ncbi.nlm.nih.gov/pubmed/24862308
- Mathew H, Dittus C, Malek A, Negroiu A. Howell-Jolly bodies on peripheral smear leading to the diagnosis of congenital hyposplenism in a patient with septic shock. Clin Case Rep 2015;3:714-717. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4551333
- Ryan FP, Smart RC, Holdsworth CD, et al. Hyposplenism in inflammatory bowel disease 1978;19:50-55. https://www.ncbi.nlm.nih.gov/pubmed/624506
- Kuchar E, Miśkiewicz K , Karlikowska M. A review of guidance on immunization in persons with defective or deficient splenic function. Br J Haematol 2015; 171:683-94. http://onlinelibrary.wiley.com/doi/10.1111/bjh.13660/full
Contributed by Katarzyna Orlewska, Medical Student, Warszawski Uniwersytet Medyczny, Poland