Diffuse changes in the pancreas: meaning, treatment and diet

The phrase "diffuse pancreatic changes" is not a diagnosis, but an ultrasound term. It describes a uniform change in the echostructure of the gland (echogenicity, homogeneity, size), which occurs in a wide range of conditions: from transient edema in acute pancreatitis to chronic fibro-fatty changes, non-alcoholic fatty infiltration (fatty pancreas), autoimmune pancreatitis, and the consequences of previous inflammatory episodes. This protocol can only be correctly interpreted by taking into account symptoms, tests, and, if necessary, additional imaging techniques. [1]

On ultrasound, diffuse changes most often manifest as increased echogenicity and/or parenchymal heterogeneity, sometimes as changes in size and contour. Modern ultrasound courses emphasize that there is no "one-size-fits-all" standard—the conclusion is influenced by age, body type, retroperitoneal fat, and the presence of concomitant fatty liver disease. Therefore, the ultrasound image is only a starting point for the clinician. [2]

The most common "benign" causes are age-related fibrofatty changes and non-alcoholic fatty pancreas disease. However, the same symptoms are also seen in early chronic pancreatitis and autoimmune pancreatitis, where timely verification determines the treatment strategy (steroids, endoscopic or surgical solutions for complications). A combination of clinical symptoms, enzymes, markers, endoscopic ultrasonography, and tomography is used to differentiate between the two. [3]

Finally, diffuse changes may be an "echo trace" of previous inflammation: foci of fibrosis, microcalcifications, moderate dilation of the duct. In these cases, the emphasis shifts to preventing progression, screening for exocrine insufficiency and metabolic disorders, and correcting risk factors (alcohol, smoking, hypertriglyceridemia, obesity). [4]

Code according to ICD-10 and ICD-11

The International Classification of Diseases does not have a separate code for "diffuse changes" per se: the code is selected based on the underlying disease that explains the ultrasound findings. For acute pancreatitis, the K85 block (ICD-10) is used, which covers a range from interstitial edema to necrosis; for chronic pancreatitis, the K86.0 (alcoholic) and K86.1 (other chronic pancreatitis) are used. Exocrine insufficiency and cystic changes have their own entries within K86. [5]

In ICD-11, acute pancreatitis is coded as DC31, and chronic pancreatic diseases are coded in the corresponding pancreatic diseases block; the choice of clarifying "postcoordinations" allows for the recording of the etiology (e.g., hypertriglyceridemia) and complications (duct stenosis, cysts). Thus, the correct code depends on the confirmed clinical diagnosis, not on the wording in the ultrasound report. [6]

Table 1. Examples of coding common causes of “diffuse changes”

Scenario (diagnosis)	ICD-10	ICD-11 (MMS)
Acute pancreatitis	K85.x	DC31 - Acute pancreatitis [7]
Alcoholic chronic pancreatitis	K86.0	(respective category of chronic diseases of the pancreas, with post-coordination) [8]
Other chronic pancreatitis	K86.1	similarly, with clarification of the causes/complications [9]
Exocrine insufficiency	K86.81 (MKD-10-CM) - in local systems	coded as a manifestation/comorbidity to the underlying condition [10]
Autoimmune pancreatitis	K86.1 (in chronic form) + clarification of etiology	"Pancreatitis, autoimmune" in the block of chronic diseases of the pancreas

Epidemiology

Acute pancreatitis is one of the most common causes of emergency hospitalization for abdominal pain; the annual incidence is high, and the severity ranges from mild to necrotizing. Diffuse decreased echogenicity and edema on ultrasound are typical in the early stages. Standardized treatment approaches (early enteral nutrition, moderate fluid resuscitation) have improved outcomes. [11]

Chronic pancreatitis is less common, but it more often causes persistent diffuse changes (fibrosis, atrophy, duct dilation). Its incidence depends on the region and the structure of risk factors (alcohol, smoking, genetics, biliary tract disease). Early forms are often recognized by a combination of endoscopic ultrasonography and clinical examination. [12]

Non-alcoholic fatty infiltration of the pancreas (NAFPD) is an increasingly recognized finding. Recent reviews estimate its prevalence to range from approximately 16 to 35 percent in the general population and is higher in obesity and metabolic syndrome. It is associated with a risk of diabetes mellitus, pancreatic insufficiency, and possibly increased cancer risk—an issue under active study. [13]

Table 2. What most often lies behind “diffuse changes” on ultrasound

Cause	Typical contexts	Comment
Acute pancreatitis	Sudden pain + ↑lipase	Edema, decreased echogenicity, increased size [14]
Chronic pancreatitis	Long history of pain, steatorrhea	Fibrosis, heterogeneity, microcalcifications, ductal changes [15]
Fatty infiltration (NAFPD)	Obesity, metabolic syndrome	Increased echogenicity, often without symptoms, “metabolic” risks [16]
Autoimmune pancreatitis	IgG4-associated disease	Diffuse "sausage-shaped" thickening, duct strictures [17]

Reasons

The main "large groups" of causes are inflammation (acute/chronic), metabolic fat infiltration, immune and post-inflammatory fibrotic changes. Acute pancreatitis is triggered by biliary obstruction, alcohol, hypertriglyceridemia, and, less commonly, medications and post-endoscopic causes. This leads to edema, which appears as a diffuse change on ultrasound. [18]

Chronic pancreatitis is the result of repeated inflammatory episodes or toxic-metabolic effects (alcohol, smoking), genetic and obstructive factors. Over time, the parenchyma is replaced by fibrosis and fat, and exocrine and endocrine functions are reduced. Ultrasound reveals diffuse heterogeneity, sometimes head/tail atrophy, and irregular contours. [19]

Non-alcoholic fatty pancreatic disease is associated with obesity, insulin resistance, and metabolic syndrome. Mechanisms include "fatty infiltration" (lipid accumulation) and "fatty replacement" (death of acinar cells with their replacement by adipocytes). It is one of the most common "asymptomatic" sources of diffuse hyperechogenicity. [20]

Autoimmune pancreatitis (IgG4-associated or type 2) can also produce diffuse changes, but here, systemic features (salivary glands, bile ducts, kidneys) and a good response to steroids are important. Magnetic resonance cholangiopancreatography and/or endoscopic ultrasonography with biopsy are often necessary for verification. [21]

Risk factors

Inflammatory risk factors include a history of acute pancreatitis, cholelithiasis, regular alcohol consumption, and smoking—the latter increases fibrosis and accelerates chronicity. Controlling these factors reduces the likelihood of progression to persistent diffuse changes. [22]

Metabolic factors include obesity (especially visceral), insulin resistance, hypertriglyceridemia, and concomitant fatty liver disease. These same factors are associated with fatty pancreas and, consequently, hyperechogenicity on ultrasound. [23]

"Immune/rare" conditions include IgG4-associated diseases and certain drug exposures. Here, the risk is determined by the underlying pathology and requires a specialized assessment. [24]

Table 3. Risk factors and what to do about them

Factor	What has been proven to help
Alcohol, smoking	Refusal → less relapse/progression of chronic pancreatitis [25]
Obesity, metabolic syndrome	Weight loss of 5-10%, control of glycemia and lipids → regression of hyperechogenicity in some patients [26]
Gallstone disease	Elective cholecystectomy after biliary pancreatitis reduces recurrence [27]
Hypertriglyceridemia	Lowering triglycerides (diet, omega-3, fibrates) reduces the risk of pancreatitis [28]

Pathogenesis

In acute pancreatitis, diffuse changes reflect edema and cellular damage due to premature enzyme activation and an inflammatory cascade (from interstitial edema to necrosis). This is accompanied by a systemic reaction and the risk of organ failure, which determines the early prognosis. [29]

In chronic pancreatitis, a fibroinflammatory process predominates: persistent inflammation activates pancreatic stellate cells, causing collagen remodeling, ductal changes, and microcalcifications. The result is diffuse heterogeneity, decreased exocrine function, and possible "pancreatogenic" diabetes mellitus. [30]

Pancreatic steatosis develops through two mechanisms: "infiltration" (fat accumulation in acinar cells in obesity) and "replacement" (fatty trabecular tissue at the site of lost acinars). It is associated with insulin resistance and can impair enzyme secretion. [31]

Autoimmune pancreatitis is an immune-mediated process with massive infiltration and fibrosis, often associated with bile duct strictures. Ultrasound imaging may show this as a diffuse thickening with smooth contours and reduced echogenicity. [32]

Symptoms

In many people, diffuse changes are an incidental finding without symptoms. In such cases, clinical management depends on risk factors and laboratory markers. In the absence of complaints and normal test results, observation and lifestyle modification are often sufficient. [33]

Symptomatic scenarios include: typical "girdle" pain and vomiting in acute pancreatitis; chronic pain, weight loss, steatorrhea and bloating in chronic pancreatitis and exocrine insufficiency; dyspepsia and metabolic manifestations in fatty infiltration; painless jaundice in autoimmune ductal disease.[34]

Red flags: persistent severe pain, fever, falling blood pressure, vomiting with dehydration, black stools or "coffee ground" vomit, progressive jaundice, rapid weight loss. These signs require urgent evaluation. [35]

Forms and stages

From the point of view of image diagnostics, it is useful to distinguish: (1) acute changes (edema/diffuse enlargement), (2) chronic fibro-fatty changes, (3) metabolic hyperechogenicity (fatty infiltration), (4) immune "diffuse" forms (autoimmune pancreatitis). Each phenotype has its own examination route. [36]

For the "early" chronic form, endoscopic ultrasonography and the Rosemont/Japanese criteria for "early chronic pancreatitis" (structural and functional signs without coarse calcifications) are used as a guide. This helps intervene before irreversible failure develops. [37]

Table 4. Diffuse changes: phenotypes and how they differ

Phenotype	Ultrasound picture	Leading tests	First steps
Acute pancreatitis	Decreased echogenicity, enlargement, edema	Lipase/amylase, CT with contrast (48-72 h)	Intensive care, nutrition, search for the cause [38]
Chronic pancreatitis	Heterogeneity, microcalcifications, duct	EUS (Rosemont), MRCP	Anesthesia, enzymes, endoscopic/surgery as indicated [39]
Fatty infiltration	Hyperechogenicity, without mass effect	Ultrasound comparison, MR methods	Weight loss, metabolic control [40]
Autoimmune	Diffuse thickening, "sausage"	IgG4, MRCP/biopsy	Steroids/immunotherapy, stricture control [41]

Complications and consequences

In chronic cases, the main long-term risk is exocrine pancreatic insufficiency (fat maldigestion, steatorrhea, vitamin deficiencies), requiring enzyme replacement therapy. Untreated insufficiency is associated with sarcopenia and a worsening prognosis. [42]

Another risk is carbohydrate metabolism disorders, including "pancreatogenic" diabetes. Regular glycemic screening is recommended for patients with chronic structural changes in the pancreas. [43]

In fatty infiltration, associations with diabetes, cardiovascular events, and increased risk of certain cancers have been discussed; this is a reason to actively monitor metabolic factors and body weight. [44]

When to see a doctor

It's worth seeking medical attention if you experience persistent heaviness/bloating after eating, episodes of "oily, shiny" stools, weight loss without dieting, unstable stool, or unexplained anemia—even if the pain is mild. These may indicate exocrine insufficiency. [45]

Immediately - in case of “acute animal” pain in the upper abdomen radiating to the back, repeated vomiting, fever, jaundice, drop in blood pressure - typical signs of acute pancreatitis and its complications. [46]

If the ultrasound report says “diffuse changes,” but there is a complicated medical history (alcohol, gallstone disease, obesity, diabetes mellitus), it is better not to postpone a specialist consultation: it is important to determine in time which group the finding belongs to. [47]

Diagnostics

Starter kit: clinical examination, pancreatic enzymes (lipase/amylase), complete blood count, C-reactive protein (if an acute process is suspected). If pain and enzymes are absent, a triage assessment includes glycemia, lipid profile, body weight, and markers of malabsorption based on complaints. [48]

Ultrasound is the first port of call: the echogenicity of the pancreas is compared with that of the spleen/kidney and liver, and the size, contours, and ducts are assessed. In case of doubt or to assess complications, magnetic resonance imaging/magnetic resonance cholangiopancreatography is used; in severe acute cases, a CT scan with contrast is performed after 48-72 hours. [49]

For "early chronic pancreatitis" and minor ductal changes, endoscopic ultrasonography with the Rosemont/Japanese Revised Criteria (2019) is optimal, increasing specificity. This is the method of choice when conventional tomography is still "normal" and clinical symptoms persist. [50]

If exocrine insufficiency is suspected, stool should be tested for elastase-1, and in severe cases, a nutritional profile (albumin, fat-soluble vitamins) should be assessed. If an autoimmune process is suspected, IgG4 should be tested and, if necessary, a targeted biopsy should be performed. [51]

Table 5. Diagnostic tools and their tasks

Method	What does it reveal?	When needed
Ultrasound	Echo pattern (fat/edema/fibrosis), size, duct	First line in most patients [52]
CT with contrast (48-72 hours)	Necrosis, complications of the acute process	Moderate/severe acute pancreatitis [53]
MRI/MRCP	Ducts, parenchyma without irradiation	Chronic and immune forms, unclear ultrasound picture
EUS (Rosemont/JPS)	Early chronic form, microstructure	Symptoms with "normal" CT/MRI [54]
Fecal elastase-1	Exocrine insufficiency	Degree of maldigestion/enzyme decision [55]

Differential diagnosis

Increased echogenicity of the pancreas differentiates between fatty infiltration and fibrosis in chronic pancreatitis: with steatosis, there is often no "mass effect" and the duct is preserved, while with fibrosis, there are often ductal changes, calcifications, and foci of atrophy. EUS and MR methods help differentiate between the two scenarios. [56]

A diffuse decrease in echogenicity and an increase in size are characteristic of an early edematous process (acute pancreatitis) or the autoimmune variant; in the latter, there may be "belts" of hypoechogenicity around the duct and a uniform thickening of the gland. Enzymes and serology/MRCP are decisive here. [57]

Be aware of "masks": infiltrative tumors, lymphoma, rare cystic-solid lesions. Any inconsistent clinical presentation or progression of changes requires extensive imaging and biopsy. [58]

Table 6. How to distinguish common "masks"

State	Pros and cons of ultrasound	What confirms
Fatty infiltration	Uniform hyperechogenicity, without mass effect	Echogenicity comparison, MR methods [59]
Chronic pancreatitis	Heterogeneity, microcalcifications, duct	EUS (Rosemont), MRCP, clinic [60]
Autoimmune	Diffuse thickening, "capsule-like"	IgG4, MRCP, biopsy [61]
Acute inflammation	Edema/enlargement, hypoechogenicity	Lipase, CT with contrast (as indicated) [62]

Treatment

1) If it is acute pancreatitis. The principles of modern therapy are: moderate infusion resuscitation with frequent reassessment, early enteral nutrition "as tolerated" (including orally), pain relief, thrombosis prevention, and, in the case of a biliary cause, timely cholecystectomy; antibiotics are given only if infection is suspected. This protocol reduces complications and mortality. [63]

2) If it is chronic pancreatitis. Multi-step plan: cessation of alcohol and smoking, nutritional support (enough protein/calories), pain management (stepwise from non-opioids to blockades/endoscopic procedures), enzyme replacement therapy for exocrine insufficiency (enzymes during meals, titration according to symptoms), treatment of complications (strictures/stones - endoscopic papillotomy, lithotripsy; ductal decompression or resection - for refractory pain/obstruction). [64]

3) If it is fatty infiltration (NAFPD). The key is non-drug correction: gradual weight loss (5-10%), aerobic activity, a Mediterranean diet, and glycemic and lipid control. According to reviews, hyperechogenicity regresses in some patients with weight loss; there are no specific "pills for fatty pancreas." Addressing cardiometabolic risk factors is important. [65]

4) If it is autoimmune pancreatitis. Induction of remission with steroids followed by maintenance/slow reduction; in case of relapses, immunosuppressants or rituximab in specialized centers. Monitoring for biliary strictures and concomitant IgG4 organ damage is mandatory. [66]

5) Exocrine insufficiency (regardless of cause). Diagnosis is confirmed by clinical findings and low fecal elastase-1; treatment includes adequate doses of encapsulated enzymes with an acid-resistant shell, and, if necessary, correction of vitamins A, D, E, and K, as well as nutritional support. The goal is to eliminate steatorrhea and prevent deficiencies. [67]

Table 7. What we treat is what we treat: a quick navigator

Scenario	First line	Escalation/special methods	Target
Acute pancreatitis	Infusion, early feeding, pain control	Endoscopy/surgery for complications	Prevent organ failure [68]
Chronic pancreatitis	Detoxification, enzymes, pain relief	Endoscopy/surgery for obstruction and pain	Symptom and nutritional management [69]
Fatty infiltration	Weight loss, metabolic control	-	Reduce echogenicity/cardiometabolic risks [70]
Autoimmune	Glucocorticosteroids	Immunosuppression/rituximab	Induce and maintain remission [71]
Exocrine insufficiency	Enzymes with food	Vitamins A, D, E, K, nutritionist	Eliminate maldigestion [72]

Nutrition and lifestyle

In acute pancreatitis, the safety of early oral nutrition has been proven based on tolerability; if this is not possible, enteral tube feeding is preferable to total parenteral nutrition. For chronic forms, adequate protein, frequent meals, and limiting very fatty fried foods during the enzyme selection period are important; strict "pancreatic diets" without evidence are not recommended. [73]

For fatty infiltration, a general metabolic approach works: 300-500 kilocalories less than the daily norm, 150 minutes of aerobic activity per week, an emphasis on vegetables/fish/whole grains, and control of sugars and saturated fats. These measures improve not only the echocardiogram but also the cardiometabolic risk profile. [74]

Alcohol and smoking are independent factors of poor prognosis for any chronic changes in the gland: complete abstinence reduces pain, exacerbations and the need for opioid analgesia. [75]

Table 8. Dietary tips (what usually helps)

Target	What to do in practice
Reduce the risk of exacerbations	Eliminate alcohol, quit smoking
Reduce steatorrhea	Take enzymes with every meal/snack, do not avoid fat completely (otherwise deficiencies)
Losing weight with NAFPD	Mediterranean pattern, minimum step 7-10 thousand/day, control of sugary drinks
Maintain nutritional status	1-1.5 g protein/kg/day for chronic pancreatitis, monitoring vitamins A, D, E, K

Prevention

Primary: control of gallstone disease (elective cholecystectomy after the first biliary pancreatitis), cessation of alcohol and smoking, correction of hypertriglyceridemia and excess weight. These measures reduce the likelihood of "new" diffuse changes of an inflammatory nature. [76]

Secondary: in chronic forms - early enzyme therapy in case of deficiency, pain management step by step, timely endoscopic examination for ductal strictures and stones, metabolic control (glucose/lipids). [77]

In case of fatty infiltration, long-term goals are weight loss and physical activity; in case of autoimmune process, supportive therapy and monitoring of concomitant IgG4 lesions. [78]

Forecast

If "diffuse changes" reflect an acute edematous process, the prognosis is usually favorable with modern protocols and the absence of complications. In chronic pancreatitis, outcome depends on pain control, nutrition, and complications; without risk factor modification, progression is likely. [79]

In case of fatty infiltration, the prognosis is usually good and is determined by the cardiometabolic profile: weight loss and correction of insulin resistance improve the indicators and reduce associated risks. [80]

Autoimmune forms have a favorable response with timely steroid/immunosuppressant therapy, but require monitoring due to relapses and ductal strictures. [81]

FAQ

"Diffuse changes" - is this serious?

In and of themselves, no, this is not a diagnosis. It is important to understand the cause: from harmless fatty infiltration to early chronic pancreatitis. The treatment strategy is determined by the clinical picture and additional tests. [82]

Is a low-fat diet always necessary?
No. With exocrine pancreatitis, proper enzyme dosages with each meal are more important than a strict low-fat diet, which can lead to deficiencies. With NAFPD, the goal is weight loss and a healthy diet. [83]

When to do CT/MRI if you already have an ultrasound?

If an acute, severe process is suspected (to assess necrosis), the picture is unclear, ductal problems exist, or an autoimmune form is suspected, MRI/MRCP or CT should be performed as indicated. Endoscopic ultrasonography is useful in the "early" chronic process. [84]

Is it possible to “cure” fatty pancreas with pills?

There are no specific medications yet; weight loss, physical activity, and diabetes/lipid control are the most effective. In some patients, echo signs regress. [85]