Chronic appendicitis is a rare, low-grade inflammation of the appendix that comes and goes over weeks, months, or even years without escalating into a medical emergency. Unlike acute appendicitis, which intensifies rapidly and typically sends people to the emergency room within hours, chronic appendicitis produces milder symptoms that flare up and then fade on their own. It accounts for roughly 7% of appendectomy cases, though the true number is likely higher because it often goes unrecognized.
How It Differs From Acute Appendicitis
Acute appendicitis follows a predictable, fast-moving pattern. Pain starts near the belly button, then shifts over several hours to the lower right abdomen. Nausea and vomiting develop, fever may follow, and the whole situation typically demands surgery within 24 to 72 hours. Left untreated, the appendix can rupture.
Chronic appendicitis doesn’t follow that script. Something irritates the appendix repeatedly, but the inflammation never builds to the point of rupture or severe illness. You might have a dull ache in your lower right abdomen for a few days, feel fine for a week or two, and then have it return. The episodes can be mild enough to dismiss as a stomach bug or something you ate. This on-and-off pattern is the defining feature, and it’s also the reason it gets missed so often.
Symptoms to Watch For
The hallmark symptom is recurring pain in the lower right side of your abdomen, in the general area about two inches inward from the bony point of your hip toward your belly button. The pain tends to be less intense than what you’d feel with acute appendicitis, more of a soreness or cramping than the sharp, escalating pain that drives an ER visit.
Other symptoms can appear during flare-ups:
- Nausea and reduced appetite
- Low-grade fever that comes and goes
- General malaise, a vague sense of feeling unwell
- Mild bloating or abdominal swelling
Between episodes, you may feel completely normal. That’s part of what makes chronic appendicitis frustrating. The symptoms are real but intermittent, and they don’t match the dramatic presentation most people associate with appendicitis. Many people live with it for months before getting a diagnosis, sometimes cycling through multiple doctor visits and tests for other conditions first.
Why It’s Hard to Diagnose
Chronic appendicitis sits in a diagnostic gray zone. The symptoms overlap with a long list of other conditions: irritable bowel syndrome, Crohn’s disease, urinary tract infections, kidney stones, ovarian cysts, endometriosis, gallbladder problems, and gastroenteritis, among others. Appendicitis in general is misdiagnosed in about 33% of women of childbearing age, with pelvic inflammatory disease and urinary tract infections being the most common wrong answers. In children, the misdiagnosis rate runs 25 to 30%, often confused with stomach flu or respiratory infections.
CT scans are the primary imaging tool, but chronic appendicitis doesn’t always look dramatic on a scan. Doctors look for an appendix wider than 6 millimeters, signs of inflammation in the surrounding fat, or the presence of a small hardened deposit called an appendicolith. In one study of patients with chronic appendiceal inflammation, CT showed an enlarged appendix (8 to 13 mm) in most but not all cases, and surrounding inflammation was visible in just over half. About 9% of patients who went to surgery based on CT findings suspicious for acute appendicitis actually turned out to have chronic inflammatory conditions instead. On imaging, chronic and acute cases can look virtually identical.
When the appendix is eventually removed, the tissue itself tells the story. Pathologists find a range of changes: chronic inflammation with clusters of immune cells, scarring and thickening of the appendix wall, and sometimes granulomas (small clumps of inflammatory tissue). These findings confirm that the appendix has been dealing with repeated, low-level irritation over time rather than a single acute event.
Conditions That Mimic Chronic Appendicitis
Because the symptoms are nonspecific, your doctor will likely consider and rule out several other possibilities before arriving at chronic appendicitis. The most commonly confused conditions include:
- Crohn’s disease, which can cause similar right-sided abdominal pain and inflammation
- Ovarian cysts or endometriosis in women, both of which cause recurring pelvic and lower abdominal pain
- Kidney stones, which can produce right-sided pain that comes and goes
- Diverticulitis, though this more commonly affects the left side
- Mesenteric adenitis, swollen lymph nodes in the abdomen that mimic appendicitis, particularly in younger people
Getting to the right diagnosis often requires a combination of imaging, blood work, and careful attention to the pattern of symptoms over time. If you’ve had repeated episodes of right-sided abdominal pain that resolve on their own, mentioning that specific pattern to your doctor can help point the evaluation in the right direction.
Treatment and What to Expect
Surgical removal of the appendix (appendectomy) is the standard treatment for chronic appendicitis, and it’s generally very effective at resolving symptoms permanently. The procedure is typically done laparoscopically, meaning a few small incisions rather than one large one, with most people going home the same day or the next.
There has been growing interest in treating uncomplicated appendicitis with antibiotics alone. In studies of children with uncomplicated acute appendicitis, antibiotics without surgery had a 67% success rate at one year, meaning about a third eventually needed an appendectomy anyway. Children treated with antibiotics had fewer days of restricted activity (about 7 days compared to 11 for surgery) and reported better quality of life in the first month, though by one year the quality-of-life differences disappeared. These findings come from acute appendicitis research, and whether antibiotics work as well for chronic cases is less clear. Given that chronic appendicitis involves repeated flare-ups by definition, most surgeons lean toward removal to prevent the cycle from continuing or eventually progressing to an acute episode.
Risks of Leaving It Untreated
Chronic appendicitis is not immediately dangerous the way acute appendicitis is. The appendix isn’t on the verge of rupturing, and individual flare-ups tend to resolve without intervention. But there are real reasons not to simply ignore it. Each episode of inflammation adds to the scarring and damage in the appendix wall, and there’s always a possibility that what has been a mild, recurring problem could tip over into acute appendicitis. Living with unpredictable bouts of abdominal pain, nausea, and general unwellness also takes a toll on daily life, especially when you don’t yet have a diagnosis and aren’t sure what’s causing it.
If you’ve been dealing with recurring lower right abdominal pain that seems to come and go without explanation, chronic appendicitis is worth raising with your doctor. It’s uncommon enough that it may not be the first thing considered, but naming the pattern of symptoms, especially that they recur in the same location and then resolve, can help move the evaluation forward.