It has been hypothesized that biofilm bacterial infections may account for many cases of antibiotic-refractory chronic sinusitis. Biofilms are complex aggregates of extracellular matrix and inter-dependent microorganisms from multiple species, many of which may be difficult or impossible to isolate using standard clinical laboratory techniques. Bacteria found in biofilms have their antibiotic resistance increased up to 1000 times when compared to free-living bacteria of the same species. A recent study found that biofilms were present on the mucosa of 75% of people undergoing surgery for chronic sinusitis.

Sinusitis is a common condition, with between 24 and 31 million cases occurring in the United States annually. Chronic sinusitis affects approximately 12.5% of people.

Causes can be remembered by mnemonic HERNIA:

- Hereditary factors: the disease runs in families

- Endocrine imbalance: the disease tends to start at puberty and mostly involves females

- Racial factors: whites are more susceptible than natives of equatorial Africa

- Nutritional deficiency: vitamins A or D, or iron

- Infection: "Klebsiella ozaenae", diphtheroids, "Proteus vulgaris", "E. coli", etc.

- Autoimmune factors: viral infection or some other unidentified insult may trigger antigenicity of the nasal mucosa.

Specific infections, such as syphilis, lupus, leprosy and rhinoscleroma, may cause destruction of the nasal structures leading to atrophic changes. Atrophic rhinitis can also result from long-standing purulent sinusitis or radiotherapy of the nose, or as a complication of surgery of the turbinates. The United Kingdom National Health Service has stated that "Most cases of atrophic rhinitis in the UK occur when the turbinates are damaged or removed during surgery". Some authors refer to as Atrophic rhinitis secondary to sinus surgery as the empty nose syndrome.

While risk factors vary with age and gender, most of the common chronic diseases in the US are caused by dietary, lifestyle and metabolic risk factors that are also responsible for the resulting mortality. Therefore, these conditions might be prevented by behavioral changes, such as quitting smoking, adopting a healthy diet, and increasing physical activity. Social determinants are important risk factors for chronic diseases. Social factors, e.g., socioeconomic status, education level, and race/ethnicity, are a major cause for the disparities observed in the care of chronic disease. Lack of access and delay in receiving care result in worse outcomes for patients from minorities and underserved populations. Those barriers to medical care complicate patients monitoring and continuity in treatment.

In the US, Minorities and low-income populations are less likely to access and receive preventive services necessary to detect conditions at an early stage.

The majority of US health care and economic costs associated with medical conditions are for the costs of chronic diseases and conditions and associated health risk behaviors. Eighty-four percent of all health care spending in 2006 was for the 50% of the population who have one or more chronic medical conditions (CDC, 2014).

There are currently no studies detailing the long term outcome of chronic granulomatous disease with modern treatment. Without treatment, children often die in the first decade of life. The increased severity of X-linked CGD results in a decreased survival rate of patients, as 20% of X-linked patients die of CGD-related causes by the age of 10, whereas 20% of autosomal recessive patients die by the age of 35.

Recent experience from centers specializing in the care of patients with CGD suggests that the current mortality has fallen to under 3% and 1% respectively.

CGD was initially termed "fatal granulomatous disease of childhood" because patients rarely survived past their first decade in the time before routine use of prophylactic antimicrobial agents. The average patient now survives at least 40 years.

A growing body of evidence supports that prevention is effective in reducing the effect of chronic conditions; in particular, early detection results in less severe outcomes. Clinical preventive services include screening for the existence of the disease or predisposition to its development, counseling and immunizations against infectious agents. Despite their effectiveness, the utilization of preventive services is typically lower than for regular medical services. In contrast to their apparent cost in time and money, the benefits of preventive services are not directly perceived by patient because their effects are on the long term or might be greater for society as a whole than at the individual level.

Therefore, public health programs are important in educating the public, and promoting healthy lifestyles and awareness about chronic diseases. While those programs can benefit from funding at different levels (state, federal, private) their implementation is mostly in charge of local agencies and community-based organizations.

Studies have shown that public health programs are effective in reducing mortality rates associated to cardiovascular disease, diabetes and cancer, but the results are somewhat heterogeneous depending on the type of condition and the type of programs involved. For example, results from different approaches in cancer prevention and screening depended highly on the type of cancer.

The rising number of patient with chronic diseases has renewed the interest in prevention and its potential role in helping control costs. In 2008, the Trust for America's Health produced a report that estimated investing $10 per person annually in community-based programs of proven effectiveness and promoting healthy lifestyle (increase in physical activity, healthier diet and preventing tobacco use) could save more than $16 billion annually within a period of just five years.

CRMO was once considered strictly a childhood disease, but adults have been diagnosed with it. The affected tends to range from 4 to 14 years old, with 10 as the median age. As stated above, CRMO occurs 1:1,000,000 and primarily in girls with a 5:1 ratio. That means out of six million, there will probably be 5 girls and 1 boy with the condition.

CGD affects about 1 in 200,000 people in the United States, with about 20 new cases diagnosed each year.

Chronic granulomatous disease affects all people of all races, however, there is limited information on prevalence outside of the United States. One survey in Sweden reported an incidence of 1 in 220,000 people, while a larger review of studies in Europe suggested a lower rate: 1 in 250,000 people.

Prognosis will depend on your child's individual disease and response to treatment. It is best to discuss the prognosis with your child's pediatric rheumatologist.

There is only very weak evidence linking to coronary heart disease.

There is little evidence linking progression of periodontal disease to low birth weight or preterm birth:

"In these women with periodontitis and within this study's limitations, disease progression was not associated with an increased risk for delivering a pre-term or a low birthweight infant."

There is recently emerged evidence linking chronic periodontitis with head and neck squamous cell carcinoma: "Patients with periodontitis were more likely to have poorly differentiated oral cavity SCC than those without periodontitis (32.8% versus 11.5%; P = 0.038)".

There is evidence to suggest that periodontal disease may play a role in the pathogenesis of Alzheimer's Disease.

Other causes or associations of disease are: a compromised immune system, environmental toxins, radiation exposure, diet and lifestyle choices, stress, and genetics. Diseases may also be multifactorial, requiring multiple factors to induce disease. For example: in a murine model, Crohn's disease can be precipitated by a norovirus, but only when both a specific gene variant is present and a certain toxin has damaged the gut.

The epidemiology of Idiopathic sclerosing mesenteritis disease is extremely rare and has only been diagnosed in about an estimated 300 patients worldwide to date (as of 2014), it is probably under diagnosed.

It can occur in children.

Since 1992, chronic gastritis lesions are classified according to the Sydney system.

A list of the more common and well-known diseases associated with infectious pathogens is provided and is not intended to be a complete listing.

This is the most common form of chronic gastritis. Involvement tends to occur in either an antral-predominant or multifocal atrophic pattern. "H. pylori" infection is also associated with development of peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue (MALT) lymphomas.

In medicine, describing a disease as acute denotes that it is of short and, as a corollary of that, of recent . The quantitation of how much time constitutes "short" and "recent" varies by disease and by context, but the core denotation of "acute" is always qualitatively in contrast with "chronic", which denotes long-lasting disease (for example, in acute leukemia and chronic leukemia). In addition, "acute" also often connotes two other meanings: onset and , such as in acute myocardial infarction (EMI), where suddenness and severity are both established aspects of the meaning. It thus often connotes that the condition is fulminant (as in the EMI example), but not always (as in acute rhinitis, which is usually synonymous with the common cold). The one thing that acute MI and acute rhinitis have in common is that they are not chronic. They can happen again (as in recurrent pneumonia, that is, multiple acute pneumonia episodes), but they are not the same ongoing for months or years (unlike chronic obstructive pulmonary disease, which is).

A noncount sense of "acute disease" refers to the acute phase, that is, a short course, of any disease entity. For example, in an article on ulcerative enteritis in poultry, the author says, "in acute disease there may be increased mortality without any obvious signs", referring to the acute form or phase of ulcerative enteritis.

Treatment consists of antibiotics, elevation of the affected limb, and compression. For persons with elephantiasis nostras who are overweight or obese, weight loss is recommended. Oral retinoids have been used to treat the cutaneous manifestations of the disease.

It is one of the seven destructive periodontal diseases as listed in the 1999 classification.

Not all acute diseases or injuries are severe, and vice versa. For example, a mild stubbed toe is an acute injury. Similarly, many acute upper respiratory infections and acute gastroenteritis cases in adults are mild and usually resolve within a few days or weeks.

The term "acute" is also included in the definition of several diseases, such as severe acute respiratory syndrome, acute leukemia, acute myocardial infarction, and acute hepatitis. This is often to distinguish diseases from their chronic forms, such as chronic leukemia, or to highlight the sudden onset of the disease, such as acute myocardial infarct.

The annual incidence of chronic pancreatitis is 5 to 12 per 100,000 persons, the prevalence is 50 per 100,000 persons.

Acute Endometritis is characterized by infection. The organisms most often isolated are believed to be because of compromised abortions, delivery, medical instrumentation, and retention of placental fragments. There is not enough evidence for the use of prophylactic antibiotics to prevent endometritis after manual removal of placental in vaginal birth. Histologically, neutrophilic infiltration of the endometrial tissue is present during acute endometritis. The clinical presentation is typically high fever and purulent vaginal discharge. Menstruation after acute endometritis is excessive and in uncomplicated cases can resolve after 2 weeks of clindamycin and gentamicin IV antibiotic treatment.

In certain populations, it has been associated with "Mycoplasma genitalium" and pelvic inflammatory disease.

Several causes of sclerosing mesenteritis have been suggested, but the principal pathophysiological mechanism is probably autoimmune. Trauma and prior surgical procedures have also been indicated as possibilities. It can be found in IgG4-related disease.

Elephantiasis nostras is a cutaneous condition, a final hypertrophic fibrosis following longstanding chronic lymphangitis.

Chronic Endometritis is characterized by the presence of plasma cells in the stroma. Lymphocytes, eosinophils, and even lymphoid follicles may be seen, but in the absence of plasma cells, are not enough to warrant a histologic diagnosis. It may be seen in up to 10% of all endometrial biopsies performed for irregular bleeding. The most common organisms are Chlamydia trachomatis (chlamydia), Neisseria gonorrhoeae (gonorrhea), Streptococcus agalactiae (Group B Streptococcus), Mycoplasma hominis, tuberculosis, and various viruses. Most of these agents are capable of causing chronic pelvic inflammatory disease (PID). Patients suffering from chronic endometritis may have an underlying cancer of the cervix or endometrium (although infectious cause is more common). Antibiotic therapy is curative in most cases (depending on underlying cause), with fairly rapid alleviation of symptoms after only 2 to 3 days.

Chronic granulomatous endometritis is usually caused by tuberculous. The granulomas are small, sparse, and without caseation. The granulomas take up to 2 weeks to develop and since the endometrium is shed every 4 weeks, the granulomas are poorly formed.

In human medicine, pyometra (also a veterinary condition of significance) is regarded as a form of chronic endometritis seen in elderly women causing stenosis of the cervical os and accumulation of discharges and infection. Symptom in chronic endometritis is blood stained discharge but in pyometra the patient complaints of lower abdominal pain.