The American Gastroenterological Association has published new guidance for the diagnosis and management of seronegative enteropathies.
Seronegative enteropathies are commonly encountered by gastroenterologists, but accurate diagnosis can be complicated by a wide array of etiologies, misinterpreted histologic findings, suboptimal serology testing, and use of immunosuppressive agents that mask serology findings, reported lead author Maureen M. Leonard, MD, of MassGeneral Hospital for Children in Boston, and colleagues.
“Previous work detailing the prevalence of seronegative celiac disease [CeD], diagnosis of seronegative villous atrophy, and management recommendations for seronegative villous atrophy are available,” the investigators wrote in Gastroenterology. “However, there is limited evidence to guide clinicians regarding the minimal serologic tests necessary, the role of the gluten-free diet in diagnosis and management, and the role of an expert pathologist in evaluating the diagnosis of seronegative enteropathy.”
Patients with seronegative enteropathy tend to a have a poorer prognosis than those with classic CeD and other causes of villous atrophy, the investigators noted, but with an accurate diagnosis, distinct therapies can be highly effective.
After a comprehensive literature review, Dr. Leonard and colleagues reached consensus on eight best practice advice statements.
First, the investigators advised clinicians to review histologic findings with an experienced pathologist specializing in gastroenterology, as an expert can ensure proper duodenal orientation, and possibly link a specific finding with an etiology, such as granulomas with Crohn’s disease, or decreased goblet cells with autoimmune enteropathy. Communications with pathologists should also incorporate medical, travel, and medication history.
“Clinicians should pay particular attention to obtaining a thorough medication history to determine whether a patient is taking an angiotensin II receptor antagonist, such as olmesartan, which has been described as causing enteropathy,” the investigators wrote. “In some cases, this has led patients to be incorrectly diagnosis with refractory CeD. Other medications, including azathioprine and mycophenolate mofetil, among others, also have been reported to cause enteropathy, which resolves with discontinuation of medication.”
According to Dr. Leonard and colleagues, histologic findings suggestive of Crohn’s disease should prompt HLA testing, which requires careful attention to detail.
“It is prudent that the gastroenterologist or CeD specialist review all alleles tested and reported (or obtain the alleles if not reported) by the laboratory because commercial and academic laboratories might not report all possible alleles associated with CeD,” they wrote.
If HLA testing is positive, then the patient should begin empiric treatment with a gluten-free diet, followed by clinical and endoscopic reassessment after 1-3 years.
If HLA testing is negative, then a battery of tests may be needed to detect alternative etiologies, such as giardiasis, small intestinal bacterial overgrowth, HIV, and others.
“In cases where an underlying cause was identified, a follow-up esophagogastroduodenoscopy with biopsy might not be indicated, according to the etiology identified, treatment, and clinical status,” the investigators wrote.
Even with a comprehensive work-up, clinicians may be unable to identify an etiology. This outcome may be relatively common, the investigators suggested, citing a study of 200 cases of seronegative villous atrophy, of which 18% had no identifiable etiology. Yet finding an etiology may ultimately be unnecessary, as 72% of idiopathic cases resolved without intervention within 9 months, suggesting transient villous atrophy.
Still, intervention is needed for clinically unstable patients with idiopathic seronegative villous atrophy. Dr. Leonard and colleagues recommended first-line treatment with budesonide, starting at 9 mg daily. Depending on clinical status and response, subsequent therapies may include azathioprine or prednisone.
The clinical practice update was commissioned and approved by the AGA. The investigators disclosed additional relationships with Takeda Pharmaceuticals, HealthMode, Anokion, and others.
SOURCE: Leonard MM et al. Gastroenterology. 2020 Sep 30. doi: 10.1053/j.gastro.2020.08.061.