There are seven types of attacks. Ninety percent of all patients have their first attack before they are 18 years old. All develop over 2–4 hours and last anywhere from 6 hours to 4 days. Most attacks involve fever.

1. Abdominal attacks, featuring abdominal pain, affect the whole abdomen with all signs of peritonitis (inflammation of abdominal lining), and acute abdominal pain like appendicitis. They occur in 95% of all patients and may lead to unnecessary laparotomy. Incomplete attacks, with local tenderness and normal blood tests, have been reported.

2. Joint attacks mainly occur in large joints, especially in the legs. Usually, only one joint is affected. 75% of all FMF patients experience joint attacks.

3. Chest attacks include pleuritis (inflammation of the pleura) and pericarditis (inflammation of the pericardium). Pleuritis occurs in 40% of patients and makes it difficult to breathe or lie flat, but pericarditis is rare.

4. Scrotal attacks due to inflammation of the tunica vaginalis occurs in up to 5% and may be mistaken for acute scrotum (i.e. testicular torsion).

5. Myalgia (rare in isolation)

6. Erysipeloid (a skin reaction on the legs, rare in isolation)

7. Fever without any of the other symptoms listed above (25%)

AA-amyloidosis with kidney failure is a complication and may develop without overt crises. AA amyloid protein is produced in very large quantities during attacks, and at a low rate between them, and accumulates mainly in the kidney, as well as the heart, spleen, gastrointestinal tract, and thyroid.

There appears to be an increase in the risk for developing particular vasculitis-related diseases (e.g. Henoch–Schönlein purpura), spondylarthropathy, prolonged arthritis of certain joints and protracted myalgia.

The hallmark clinical sign of effusive FIP is the accumulation of fluid within the abdomen or chest, which can cause breathing difficulties. Other symptoms include lack of appetite, fever, weight loss, jaundice, and diarrhea.

Dry FIP will also present with lack of appetite, fever, jaundice, diarrhea, and weight loss, but there will not be an accumulation of fluid. Typically a cat with dry FIP will show ocular or neurological signs. For example, the cat may develop difficulty in standing up or walking, becoming functionally paralyzed over time. Loss of vision is another possible outcome of the disease.

Individuals with CPH suffer multiple short, severe headaches a day, often more than five, with most lasting between 5 and 30 minutes each. When compared to cluster headaches, CPH attacks are typically shorter. Each headache is centered around the eye, temple and forehead and is localized to one side of the head. While redness and watering of the eye are associated with CPH, patients typically do not experience nausea or vomiting.

A common complaint among patients with cold agglutinin disease is painful fingers and toes with purplish discoloration associated with cold exposure. In chronic cold agglutinin disease, the patient is more symptomatic during the colder months.

Cold agglutinin mediated acrocyanosis differs from Raynaud phenomenon. In Raynaud phenomena, caused by vasospasm, a triphasic color change occurs, from white to blue to red, based on vasculature response. No evidence of such a response exists in cold agglutinin disease.

Other symptoms

- Respiratory symptoms: May be present in patients with "M pneumoniae" infection.

- Hemoglobinuria (the passage of dark urine that contains hemoglobin), A rare symptom that results from hemolysis, this may be reported following prolonged exposure to cold, hemoglobinuria is more commonly seen in paroxysmal cold hemoglobinuria.

- Chronic fatigue, Due to anemia.

Many secondary conditions have been reported to be possible causes of CPH, according to Mehta et al., most of which are arterial abrasions or tumors. These include aneurysms in the circle of Willis, middle cerebral artery infarction, parietal arteriovenous malformation, cavernous sinus and petrous ridge meningiomas, pituitary adenoma, Pancoast tumor, gangliocytoma of the sella turcica, and malignant frontal tumors. This accentuates the urgency for those diagnosed with CPH to receive an MRI head scan.

Signs and symptoms of typhlitis may include diarrhea, a distended abdomen, fever, chills, nausea, vomiting, and abdominal pain or tenderness.

Cold agglutinins develop in more than 60% of patients with infectious mononucleosis, but hemolytic anemia is rare.

Classic chronic cold agglutinin disease is idiopathic, associated with symptoms and signs in relation to cold exposure.

Causes of the monoclonal secondary disease include the following:

- B-cell neoplasms - Waldenström macroglobulinemia, lymphoma, chronic lymphoid leukemia, myeloma

- Non hematologic neoplasms

Causes of polyclonal secondary cold agglutinin disease include the following:

- Mycoplasma infections.

- Viral infections: Infectious mononucleosis due to Epstein-Barr virus (EBV) or CMV, Mumps, varicella, rubella, adenovirus, HIV, influenza, hepatitis C.

- Bacterial infections: Legionnaire disease, syphilis, listeriosis and "Escherichia coli."

- Parasitic infections: Malaria and trypanosomiasis.

- Trisomy and translocation: Cytogenetic studies in patients with cold agglutinin disease have revealed the presence of trisomy 3 and trisomy 12. Translocation (8;22) has also been reported in association with cold agglutinin disease.

- Transplantation: Cold agglutinin–mediated hemolytic anemia has been described in patients after living-donor liver transplantation treated with tacrolimus and after bone marrow transplantation with cyclosporine treatments. It is postulated that such calcineurin inhibitors, which selectively affect T-cell function and spare B-lymphocytes, may interfere with the deletion of autoreactive T-cell clones, resulting in autoimmune disease.

- Systemic sclerosis: Cold agglutinin disease has been described in patients with sclerodermic features, with the degree of anemia being associated with increasing disease activity of the patient’s systemic sclerosis. This may suggest a close association between systemic rheumatic disease and autoimmune hematologic abnormalities.

- Hyperreactive malarial splenomegaly: Hyperreactive malarial splenomegaly (HMS) is an immunopathologic complication of recurrent malarial infection. Patients with HMS develop splenomegaly, acquired clinical immunity to malaria, high serum concentrations of anti-"Plasmodium" antibodies, and high titers of IgM, with a complement-fixing IgM that acts as a cold agglutinin.

- DPT vaccination: Diphtheria-pertussis-tetanus (DPT) vaccination has been implicated in the development of autoimmune hemolytic anemia caused by IgM autoantibody with a high thermal range. A total of 6 cases have been reported; 2 followed the initial vaccination and 4 followed the second or third vaccinations.

- Other: Equestrian perniosis is a rare cause of persistent elevated titers of cold agglutinins. Also rarely, the first manifestations of cold agglutinin disease can develop when a patient is subjected to hypothermia for cardiopulmonary bypass surgery.

Clostridial necrotizing enteritis (CNE), also called enteritis necroticans and pigbel, is an often fatal type of food poisoning caused by a β-toxin of "Clostridium perfringens", Type C. It occurs in some developing countries, but was also documented in Germany following World War II. The toxin is normally inactivated by certain proteolytic enzymes and by normal cooking, but when these protections are impeded, the disease emerges.

The condition is usually caused by Gram-positive enteric commensal bacteria of the gut (gut flora). "Clostridium difficile" is a species of Gram-positive bacteria that commonly causes severe diarrhea and other intestinal diseases when competing bacteria are wiped out by antibiotics, causing pseudomembranous colitis, whereas Clostridium septicum is responsible for most cases of neutropenic enterocolitis.

Typhlitis most commonly occurs in immunocompromised patients, such as those undergoing chemotherapy, patients with AIDS, kidney transplant patients, or the elderly.

The characteristic symptom of Degos disease is the development of papules. Initially, individuals may have skin lesions or rashes, but they will proceed to develop distinct bumps, or papules. Papules are circular in shape, have a porcelain-white center and red border. As papules age, the white centers will skin in and only the border will remain raised. Typically, papules range from 0.5 to 1 cm in width. Papules appear on the trunk and upper extremities and are not found on the individual's palms, soles, scalp, or face.

Depending on whether an individual has the benign variant or malignant variant of the disease symptoms will vary. Both the benign and malignant forms have development of the characteristic papules. Individuals with the benign form will have the typical papules persisting anywhere from a few years to throughout their whole lives. In the benign form, no inner organs are affected. If an individual develops the malignant form, it means that not only are the papules present, but inner organs are involved. Most malignant cases involve problems of the gastrointestinal tract leading to small intestine lesions, abdominal pain, diarrhea, and bowel perforation. If the central nervous system is involved, symptoms can include headaches, dizziness, seizures, paralysis of cranial nerves, weakness, stroke, damage to small areas of the brain due to artery blockage (cerebral infarcts, and cerebral hemorrhage). Additional organs commonly impacted include the heart, lungs, and kidneys. Symptoms that may develop from damage to these organs include double vision (diploplia), clouding of lenses of eyes, swelling of the optic disc (papilledema), partial loss of vision, shortness of breath, chest pain, epilepsy,and thickening of pericardium.

Someone with the benign form may suddenly develop symptoms of the malignant form. Symptoms can last anywhere from a few weeks to several years. Onset of symptoms typically begins to manifest between the ages of 20-50. A few cases of this condition in newborns have also been described.

Streptococcus species are the cause of opportunistic infections in poultry leading to acute and chronic conditions in affected birds. Disease varies according to the Streptococcal species but common presentations include septicaemia, peritonitis, salpingitis and endocarditis.

Common species affecting poultry include:

- "S. gallinaceus" in broiler chickens

- "S. gallolyticus" which is a pathogen of racing pigeons and turkey poults

- "S. dysgalactiae" in broiler chickens

- "S. mutans" in geese

- "S. pluranimalium" in broiler chickens

- "S. equi subsp. zooepidemicus" in chickens and turkeys

- "S. suis" in psittacine birds

CNE is a necrotizing inflammation of the small bowel (especially the jejunum but also the ileum). Clinical results may vary from mild diarrhea to a life-threatening sequence of severe abdominal pain, vomiting, bloody stool, ulceration of the small intestine with leakage (perforation) into the peritoneal cavity and possible death within a single day due to peritonitis. Many patients exhibit meteorism. Treatment involves suppressing the toxin-producing organisms with antibiotics such as penicillin G or metronidazole. About half of seriously ill patients require surgery for perforation, persistent intestinal obstruction, or failure to respond to the antibiotics. An investigational toxoid vaccine has been used successfully in some developing countries but is not available outside of research.

Post-mortem findings include friable internal organs, abdominal effusion and evidence of sepsis in the joints, heart valves and brain.

Bacteria can usually be cultured from tissues collected at necropsy or identified by microscope examination.

Benign paroxysmal vertigo of childhood is an uncommon neurological disorder which presents with recurrent episodes of dizziness. The presentation is usually between the ages of 2 years and 7 years of age and is characterised by short episodes of vertigo of sudden onset when the child appears distressed and unwell. The child may cling to something or someone for support. The episode lasts only minutes and resolves suddenly and completely. It is a self-limiting condition and usually resolves after about eighteen months, although many go on to experience migrainous vertigo (or vertiginous migraine) when older.

Benign paroxysmal vertigo of childhood is a migrainous phenomenon with more than 50% of those affected having a family history of migraines affecting a first-degree relative. It has no relationship to benign paroxysmal positional vertigo which is a different condition entirely.

Trigeminal autonomic cephalgia (TAC) is the name for a type of primary headache that occurs with pain on one side of the head in the trigeminal nerve area and symptoms in autonomic systems on the same side, such as eye watering and redness or drooping eyelids. TACs include

- Cluster headache

- Paroxysmal hemicrania (chronic or episodic)

- Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)

- Short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA)

- Long-lasting autonomic symptoms with hemicrania (LASH)

TACs can be differentiated by the length and frequency of recurrence of the headaches.

Treatment for TACs varies depending on the exact type, but can include medication such as Indomethacin (in the case of chronic paroxysmal hemicrania) or acute and prophylactic therapy (in the case of cluster headache).

Clinical evaluation and identification of characteristics papules may allow a dermatologist to diagnose Degos disease. The papules have a white center and are bordered with a red ring. After lesions begin to appear, the diagnosis for Degos disease can be supported by histological findings. Most cases will show a wedge-shaped connective tissue necoris in the deep corium. This shape is due to the blockage/occlusion of small arteries.

Individuals may be diagnosed with the benign form if only the papules are present. However, an individual may be diagnosed with the malignant form if involvement of other organs like the lungs, intestine and/or central nervous system occurs. The malignant, or systematic form of this condition may suddenly develop even after having papules present for several years. In order to quickly diagnose this shift to the malignant variant of the disease, it is important for individuals to have consistent follow-up evaluations.In these evaluations, depending on which organs are suspected to be involved, the following procedures and tests may be conducted: skin inspection, brain magnetic resonance tomography, colonoscopy, chest X-ray, and/or abdominal ultrasound.

Vertigo is a medically recognized term for the symptom of vestibular system disturbance. It may include a feeling of rotation or illusory sensations of motion or both. The general term dizziness is used by nonmedical people for those symptoms but often refers to a feeling of light-headedness, giddiness, drowsiness, or faintness, all of which must be differentiated from true vertigo, since the latter symptoms might have other causes.

Motion sickness occurs more frequently in migraine patients (30–50% more than in controls). Benign paroxysmal vertigo of childhood is an example of migraine-associated vertigo in which headache does not often occur. Basilar artery migraine (BAM) consists of two or more symptoms (vertigo, tinnitus, decreased hearing, ataxia, dysarthria, visual symptoms in both hemifields or both eyes, diplopia, bilateral paresthesias, paresis, decreased consciousness and/or loss of consciousness) followed by throbbing headache. Auditory symptoms are rare. However, a study showed a fluctuating low-tone sensorineural hearing loss in more than 50% of patients with BAM with a noticeable change in hearing just before the onset of a migraine headache. The attacks of vertigo are usually concurrent with the headache and the family history is usually positive. The diagnostician must rule out: TIAs, and paroxysmal vestibular disorder accompanied by headache.

There is also a familial vestibulopathy, familial benign recurrent vertigo (fBRV), where episodes of vertigo occur with or without migraine headache. Testing may show profound vestibular loss. The syndrome responds to acetazolamide. Familial hemiplegic migraine (FHM) has been linked to mutations in the calcium channel gene. (Ophoff et al. 1966 cf. Lempert et al.)

The specific and familial association of BIFE and PKC defines a novel clinical entity : the infantile convulsions and choreoathetosis syndrome. The first observation was made in four families where children were affected with nonfebrile convulsions at age 3–12 months.Partial epileptic seizures started with a psychomotor arrest and a deviation of the head and eyes to one side, followed inconstantly by unilateral jerks.In some cases, seizures generalized secondarily. None of the interictal electroencephalograms showed epileptiform abnormalities, and magnetic-resonance imaging were normal. These convulsions had a favorable outcome. At 5–8 years of age affected children developed abnormal movements. They presented with twisting movements of the hands of a reptilian type when stressed or embarrassed. They also developed jerky movements of the legs after running. Initially, abnormal movements were intermediate in speed between quick and slow, typical of paroxysmal choreoathetosis. Combinations of abnormal movements involving the arms, legs, trunk and occasionally the head were observed. The attacks lasted only a few minutes, occurring with a frequency of 5-30 episodes per day and were not accompanied by unconsciousness. In all patients, abnormal movements disappeared at 25–30 years of age without any treatment. Since the first report similar clinical presentations have been published which confirm the specificity of the ICCA syndrome.

The defining characteristic of BPT is a tilting of an infant’s head in recurrent episodes, for varying periods of time. Furthermore, the child’s trunk may bend in the same direction as the head, giving the baby an overall curved shape; this complaint is known as tortipelvis. In addition to this, the individual may also, but not necessarily, experience vomiting, pallor, ataxia, agitation, infantile migraine, unsteadiness of gait upon learning to walk, general malaise and nystagmus.

The periods in which the child’s head is tilted and other symptoms appear can last anywhere from a few minutes to a few weeks, with a frequency of anywhere from two per year to two per month.

Benign paroxysmal positional vertigo - Migraine is commonly associated with BPPV, the most common vestibular disorder in patients presenting with dizziness. The two may be linked by genetic factors or by vascular damage to the labyrinth.

Ménière's disease - There is an increased prevalence of migraine in patients with Ménière's disease and migraine leads to a greater susceptibility of developing Ménière’s disease. But they can be distinguished. Ménière's disease may go on for days or even years, while migraines typically do not last longer than 24 hours.

Motion sickness is more prevalent in patients with migraine.

Psychiatric syndromes Dizziness and spinning vertigo are the second most common symptom of panic attacks, and they can also present as a symptom of major depression. Migraine is a risk factor for developing major depression and panic disorder and vice versa.

Infantile convulsions and choreoathetosis (ICCA) syndrome is a neurological genetic disorder with an autosomal dominant mode of inheritance. It is characterized by the association of benign familial infantile epilepsy (BIFE) at age 3–12 months and later in life with paroxysmal kinesigenic choreoathetosis. The ICCA syndrome was first reported in 1997 in four French families from north-western France and provided the first genetic evidence for common mechanisms shared by benign infantile seizures and paroxysmal dyskinesia. The epileptic origin of PKC has long been a matter of debates and PD have been classified as reflex epilepsies.Indeed, attacks of PKC and epileptic seizures have several characteristics in common, they both are paroxysmal in presentation with a tendency to spontaneous remission, and a subset of PKC responds well to anticonvulsants. This genetic disease has been mapped to chromosome 16p-q12. More than 30 families with the clinical characteristics of ICCA syndrome have been described worldwide so far.

While not the same in all people, there are several common triggers that can precipitate an attack:

- Moderate to high consumption of stimulants, such as alcohol, caffeine, or nicotine.

- Low amounts of energy due to hunger, lack of sleep, illness, or physical fatigue.

- Moderate to high presence of stress.

- Menstruation and ovulation.

Subphrenic abscess is a disease characterized by an accumulation of infected fluid between the diaphragm, liver, and spleen. This abscess develops after surgical operations like splenectomy.

Presents with cough, increased respiratory rate with shallow respiration, diminished or absent breath sounds, hiccups, dullness in percussion, tenderness over the 8th–11th ribs, fever, chills, anorexia and shoulder tip pain on the affected side. Lack of treatment or misdiagnosis could quickly lead to sepsis, septic shock, and death. It is also associated with peritonitis.