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Abstract
This is an unusual case of a middle-aged, immunocompetent man who developed toxic megacolon (TM) secondary to infection with a normally harmless bug, Campylobacter jejuni. He presented with diarrhoea, fever and abdominal pain. Faecal cultures were positive for C. jejuni. However, the patient did not show significant improvement after a trial of intravenous antibiotics. Bowel segment dilation on a CT scan combined with systemic signs (fever) led to the diagnosis of TM. A subtotal colectomy was planned but an unexpected positive response to conservative therapy deferred the surgery. Our case emphasises the crucial role that bowel rest and good nutritional support play in treating TM of infectious aetiology and how it can help avoid the need for a life-altering subtotal colectomy and ileostomy. For such presentations we also highlight how empirical steroid therapy or diagnostic sigmoidoscopy for suspected underlying ulcerative colitis can be detrimental to patient outcomes.
- infection (gastroenterology)
- inflammatory bowel disease
- medical management
- foodborne infections
- parenteral / enteral feeding
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- infection (gastroenterology)
- inflammatory bowel disease
- medical management
- foodborne infections
- parenteral / enteral feeding
Background
Campylobacter is the leading cause of bacterial diarrhoea worldwide, affecting approximately 25–30 per 100 000 people.1 In the UK alone, it accounts for an estimated 500 000 cases annually.2 Most of these cases follow a typical clinical course; an acute diarrhoeal illness which is usually self-limiting.3 Immunosuppressed individuals experience a severe or prolonged disease course.4 We present an unusual case of Campylobacter jejuni-induced toxic megacolon (TM) in an immunocompetent individual which responded to conservative treatment.
TM is defined as non-obstructive segmental or total colonic distension of ≥5.5 cm in the presence of systemic toxicity.5 It typically arises as a complication of inflammatory bowel disease (IBD) or Clostridium difficile-associated colitis6 and cases associated with Campylobacter are quite rare. There are only 14 case reports describing TM in the setting of Campylobacter infection and most were published before 2000.7 8 Over half of these cases were treated surgically, in contrast to our patient, who improved with conservative therapies.
This case demonstrates the benefits of close monitoring of a patient infected with a normally harmless organism, and emphasises the need to consider bowel rest and parenteral nutrition early in cases refractory to optimum medical management, as it may potentially help avoid more invasive and life-altering procedures.
Case presentation
This is the case of a middle-aged man who presented with diarrhoea, abdominal cramps, lethargy, loss of appetite and weight loss for the past 12 days. He denied recent antibiotic use or travel to forests, lakes or abroad; however, he did eat out frequently. Medical, family and drug history was unremarkable. On inspection, he looked pale and sick but was oriented to time, place and person. He was feverish (38.4°C), with a respiratory rate of 22 breaths per minute, but was otherwise vitally stable. Peripheries were cold and he appeared dehydrated. Abdominal examination revealed tenderness and guarding in the left lower quadrant and hyperactive bowel sounds. No per rectal bleed was noted. All other systemic examinations were unremarkable.
Investigations
On presentation, he had high inflammatory markers (white blood cell count 16.0 × 109/L and C-reactive protein 429.8 mg/L), an electrolyte imbalance (Na 124 mmol/L), low creatinine (56 µmol/L) and low albumin (28 g/L). An abdominal X-ray revealed a dilated transverse and descending colon with no air-fluid levels. Chest X-ray showed normal lung fields with no gas under the diaphragm. CT abdomen-pelvis was suggestive of modest pancolitis with no complicating features. Faeces culture grew C. jejuni. Other common pathogens such as Shigella, Salmonella and Escherichia coli O157 were excluded using various faeces culture media. Stool microscopy excluded Entamoeba. Combined enzyme immunoassays excluded Giardia and Cryptosporidium antigens in stool. Clostridium difficile was also excluded on three consecutive stool enzyme-linked immunosorbent assays. He tested negative for HIV. Both blood and urine cultures showed no bacterial growth after 48 hours of incubation.
Differential diagnosis
The top differential diagnosis to exclude was IBD. Faecal calprotectin could not be tested as the stools were so frequent and loose that the gut transit time was insufficient to allow the protein to collect to a detectable level in the stool. A careful clinical assessment was made of the ocular, oral, musculoskeletal and dermatological systems to look for extraintestinal manifestations of IBD. The patient was noted to have developed symmetrical, erythematous, non-blanching patches on the lower limbs (see figure 1). The rash resolved by itself; however, it begged the question of whether this was an extraintestinal manifestation of IBD or of Campylobacter infection. Given the high risk of perforation, a sigmoidoscopy was not attempted and hence IBD could not be fully excluded during the acute phase of the illness. The growth of Campylobacter on stool culture provided evidence for infective colitis and other common organisms were also excluded. Finally, the patient was not on medications that might have resulted in TM and potassium levels remained within normal range throughout admission.
An erythematous, non-blanching patch on the right ankle.
Treatment
He received a single dose of intravenous amoxicillin, metronidazole and gentamicin as empiric therapy, along with intravenous crystalloids to correct his hydration status and symptomatic treatment for his fever, nausea and abdominal pain. Intravenous clarithromycin 500 mg two times a day was initiated as empiric treatment for severe Campylobacter enteritis but no significant clinical improvement was observed after 6 days. Antibiotics were changed to intravenous ertapenem 1 g once a day, but this too did not bring about significant improvement and was stopped after 7 days.
His temperature spiked on day 8 of admission (38.2°C). Repeat abdominal X-ray was suggestive of colitis and dilation in the transverse colon, suspicious of TM. A subsequent CT abdomen-pelvis showed a dilation of 7 cm of the transverse colon. This, combined with signs of systemic toxicity, confirmed the diagnosis of TM. He was immediately kept nil by mouth for a day. A significant drop in CRP was observed over 24 hours from 218.3 mg/L to 128.6 mg/L. Considering this improvement, the surgical team deferred surgical intervention and restarted his feed.
His temperature spiked again on day 16 of admission and he developed excruciating left-sided abdominal pain. CT abdomen-pelvis on the 16th day showed a segmental bowel loop dilation of 9.3 cm (see figure 2). Medical therapy was declared to have failed, and a subtotal colectomy with end ileostomy was planned as a fast-track elective procedure. He was kept on bowel rest and total parenteral nutrition (TPN) was initiated through a peripherally inserted central catheter (PICC) with a 6 g nitrogen bag at 35 mL/hour. However, a significant improvement in clinical and biochemical parameters (CRP dropped from 248.3 mg/L to 87.2 mg/L) was observed over the next 72 hours. CT abdomen-pelvis showed a reduction in the size of bowel segments for the first time since admission (transverse colon calibre 6.2 cm).
A CT image of the dilated transverse colon.
On day 23 of admission, the patient again spiked a fever (38.8°C) and became hypotensive (70/40 mm Hg). He was resuscitated with intravenous crystalloids and given an empirical dose of intravenous teicoplanin for suspected catheter-related bloodstream infection. Central and peripheral blood cultures confirmed the growth of coagulase-negative Staphylococcus species. The PICC was removed and regular linezolid 600 mg two times a day was given. An echocardiogram did not show evidence of infective endocarditis. Linezolid was stopped after 10 days when follow-up blood cultures were negative for growth of any organisms after 48 hours of incubation.
Outcome and follow-up
A repeat CT abdomen-pelvis on day 31 of admission showed an improvement in the transverse colon which was now 4 cm in calibre. Subsequently, flexible sigmoidoscopy was attempted and revealed a normal mucosa from anus to distal descending colon. The biopsy showed no signs of IBD or dysplasia. The patient was now eating a regular diet and bowel movements had settled. He was discharged with no medications to take home and was planned to be followed up in 6 weeks.
Discussion
C. jejuni is a major public health problem in England, with a rising incidence despite food hygiene awareness efforts made by national organisations.9 While hydration and electrolyte correction remain the cornerstone of therapy for most, some clinical situations warrant the use of antibiotics. In our case, the patient had a protracted 12-day history of severe symptoms that fit the criteria for antibiotic use. The first-line antibiotic for confirmed C. jejuni infection as per the latest NICE guidelines is clarithromycin.10 11 However, we changed to ertapenem after poor initial response to the macrolide, which had the additional advantage of once-a-day dosing. A fluroquinolone was not used out of fear of antibiotic resistance.12
While TM is a potential complication of any inflammatory condition of the colon, it is usually associated with severe IBD or Clostridium difficile pseudomembranous colitis.6 13 14 It has a frightening overall mortality rate of 19%, and 41% in cases of perforation.15 While individuals with comorbidities like renal failure and hypertension are at higher risk of progressing to TM,16 our patient did not have any of these. Interestingly, neither did most of the other known cases of TM secondary to Campylobacter. It is postulated that TM results from a loss of smooth muscle tone in the colon, which commonly results from the transmural spread of acute mucosal inflammation. One of the implicated chemical mediators is nitric oxide.17 It is differentiated from other pathologies that may precipitate colonic dilation, like Ogilvie syndrome, by the presence of systemic toxicity.6 In addition to having a transverse colon diameter of 9.3 cm, our patient suffered from fever, anaemia, leucocytosis, hypotension, electrolyte imbalance and low albumin, fitting the diagnostic criteria for TM.18
An obvious differential diagnosis to exclude in this case was IBD. In addition to the clinical context, an endoscopic and histological evaluation is necessary to rule out Crohn’s and ulcerative colitis.19 However, given the radiological evidence of bowel loop dilation we felt it was unsafe to scope the patient for diagnostic purposes due to the risk of impending perforation. Empirical steroids were avoided because of the risk of masking peritoneal signs; an indicator for surgical intervention. We noted worse outcomes in previous similar cases where empirical steroids were used.20–23 Instead, we used serial CT scans and frequent clinical re-evaluation to monitor for perforation and progressive bowel loop dilation. A flexible sigmoidoscopy was attempted after the patient had shown significant reduction in bowel diameter and definitively excluded IBD after histological examination of biopsy specimens.
Indications for surgical intervention include perforation, progressive bowel loop dilation and clinical deterioration.24 The latter two were present on two occasions during the clinical course of this patient and a surgical evaluation was completed for subtotal colectomy with end ileostomy. However, both times the patient showed significant clinical and biochemical improvement after being kept on bowel rest. Such a sustained improvement with bowel rest and TPN was unique to our case compared with all the previous known case reports where parenteral nutrition was used.8 21 23 While the literature is rich in dietary interventions for IBD, the effect of bowel rest and TPN in cases of infective colitis complicated by TM refractory to medical treatment has not been thoroughly researched. We theorise that bowel rest allowed for effective decompression of the colon, reducing the risk of perforation and the TPN helped to nutritionally replenish the patient.
Cutaneous lesions are rare in C. jejuni infections. The pathophysiology behind these skin lesions is unknown but may be distinct for every lesion. According to Roberts et al,25 erythema nodosum and cellulitis were commonly associated with Campylobacter infection. However, the rash seen in our patient was not a typical pattern for either of those. We speculate it could have been the result of immunological sequelae of severe Campylobacter infection, particularly a leucocytoclastic vasculitis. However, due to lack of an in-house dermatology facility we were unable to investigate this further.
Like previous similar cases, the development of TM in our patient was preceded by a prolonged course of diarrhoeal illness. But unlike most of these cases, he did not require surgical intervention for complete recovery. A common recurring theme in all cases that required surgical intervention was the use of empiric steroids and the decision to go for either colonoscopy or sigmoidoscopy. However, the clinical course of our patient was complicated by the development of PICC-associated sepsis. The systemic upset resulting from this line sepsis was difficult to differentiate from worsening toxicity from the megacolon. The growth of coagulase-negative Staphylococci on blood cultures and quick response to pathogen-directed therapy allowed differentiation between the two. Catheter-related bloodstream infections are one of the few risks associated with TPN26 27 and should be taken into consideration so as not to wrongfully attribute systemic toxicity to treatment failure instead of a treatable iatrogenic cause.
Learning points
Campylobacter-associated diarrhoea is a self-limiting illness in most cases; however, life-threatening toxic megacolon should be considered as a possible sequela in all patients unresponsive to initial medical therapy.
The use of empiric steroids with an infective aetiology can lead to worse outcomes and should be avoided till there is evidence suggestive of an inflammatory cause.
Diagnostic scoping of a patient with dilated bowel loops on radiology leads to worse outcomes and should be avoided till response to therapy is evident.
The use of extended bowel rest and total parenteral nutrition preoperatively can allow for effective decompression and nutritional repletion, leading to better outcomes.
Skin rashes are a rare manifestation of severe Campylobacter infection which warrant the prolonged use of antibiotics.
Ethics statements
Patient consent for publication
Acknowledgments
We would like to thank Dr Nazar Ulla Syed (Consultant Infectious Diseases) for being the clinical lead in managing this case. His evidence-based approach and clinical judgement led to a very successful outcome for this complex case. We would also like to acknowledge the efforts of our gastroenterology and surgery teams and thank them for their support. Finally, we extend our gratitude to the entire multidisciplinary team that helped care for this patient and played a valuable role in improving his outcome.
References
Footnotes
Contributors SWUH and SNA are joint first authors and were equally responsible for the planning and design of this case report. Acquisition of patient data from the case notes was performed by SWUH and MI. An extensive literature search was conducted by SNA. The case presentation was written by SWUH, NUS wrote the summary while SNA wrote the background. The discussion was authored by SWUH and SNA. NUS and MI played a supervisory role in writing up the case report. All four authors proofread the report for any errors and omissions.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Case reports provide a valuable learning resource for the scientific community and can indicate areas of interest for future research. They should not be used in isolation to guide treatment choices or public health policy.
Competing interests None declared.
Provenance and peer review Not commissioned; externally peer reviewed.