1. Chagas disease
   Depression
2. GERD (gastroesophageal reflux disease)

Though GERD can cause nausea, sore throats and chest pain, constipation is not typically associated with it. Depression and Chagas disease can both cause constipation.

1. Middle ear infection
   Anemia
2. High blood pressure

Dizziness is a symptom of all these conditions, but a fever is indicative of a middle ear infection.

1. Gastroenteritis (stomach flu)
   Irritable Bowel Syndrome
2. Gallstones

Though all these conditions list bloating as a symptom, Gastroenteritis is the only one that can also cause a loss of appetite.

1. 15 percent
   20 percent
2. More than 20 percent

The study found that 26 percent of cases were misdiagnosed, which is a fair number considering other studies have found up to 40 percent of patients are misdiagnosed.

1. Appendectomy
   Hysterectomy
2. Angioplasty

According to a University of Washington study, even with tests like computed tomography (CT), ultrasound and laparoscopy, appendicitis is misdiagnosed in 15 percent of patients.

1. Yellow Nail Syndrome
   Lymphedema
2. Fungal Infection

A rare disorder, Yellow Nail Syndrome causes extreme yellowing of the fingernails and toenails and swelling of body tissue due to a buildup of protein-rich fluid.

1. Ant attack
   Spider bite
2. Mosquito bite

Though all these bites begin with a raised, red bump, spider bites are typically combined with a red circle surrounding the bite. Most are harmless, but if you develop a fever or chills or a fluid-filled blister, go to a doctor. These symptoms may signal a poisonous spider bite.

1. Hyponatremia
   Graves Disease
2. Wilson's Disease

Wilson’s Disease, a genetically inherited disorder, is caused by a buildup of copper in the body’s tissues. If left untreated, it can cause liver disease, dysfunction of the central nervous system and even death.

1. Testicular Cancer
   Variocele
2. Hydrocele

All these diseases share a symptom: a lump or swelling on the testes. However, while varioceles and hydroceles are painless, testicular cancer patients complain of dull aches and pain around the lump.

1. Do hand tremors run in your family?
   How much caffeine do you drink?
2. Are you eating enough protein?

Protein doesn't affect the central nervous system. However, hand tremors can run in the family, and drinking too much caffeine can exacerbate symptoms.

1. Leukemia
   Scurvy
2. Brushing his teeth too hard

Though there are many other signs, pale complexion, bruising, and bleeding gums are common symptoms of leukemia.

1. Stroke
   Creutzfeldt Jakob Disease
2. Ataxia (Louis-Bar Syndrome)

Obesity and smoking both put people at risk for strokes. Though all conditions include lack of coordination as a symptom, ataxia is most common in children and Creutzfeldt Jakob disease is only found in one out of one million people.

1. Fucosidosis
   Maffucci Syndrome
2. Ollier Disease

Maffucci Syndrome, named after Italian pathologist Angelo Maffucci, is characterized by the presence of cartilage cysts and red, benign tumors called hemangioma.

1. Degos Disease
   Kohlmeier Disease
2. Both

Degos Disease, or Kohlmeirer Disease, is an extremely rare disorder in which small and medium-sized arteries become blocked. This restriction of blood flow causes skin lesions that can last from weeks to years. Extreme cases can affect multiple organs causing abdominal pain, diarrhea and/or weight loss.

1. Seasonal Affective Disorder
   Kleine-Levin Syndrome
2. Narcolepsy

Kleine-Levin Syndrome is found primarily in adolescent males. An exact cause is unknown, but scientists believe the desire to oversleep and overeat is caused by a malfunction of the hypothalamus in the brain.

1. Acromegaly
   Cushing Syndrome
2. Hypopituitarism

Acromegaly is a slow-developing disorder of the pituitary gland that causes the enlargement of certain body parts. Extreme cases can result in gigantism.

1. Angelmand Syndrome
   Rett Syndrome
2. Autism

Rett Syndrome is a rare neurodevelopmental disorder that appears mostly in females. Children with the disorder typically show no signs until seven to 18 months of age when they may begin to lose motor skills and the ability to communicate.

1. Filariasis
   Lymphedema
2. Influenza

Filariasis is an infectious disease, commonly acquired in the tropics, by small, threadlike parasites that are often transmitted to humans by mosquitos. Patients suffer from flu-like symptoms initially before their lymph nodes become obstructed, cause swelling of the extremities.

1. Dermatitis
   Gout
2. Buerger's Disease

Buerger’s Disease, primarily found in young or middle-aged men who smoke tobacco, causes a narrowing and blockage of veins leading to the extremities.

1. Pseudogout
   Lupus
2. Schnitzler Syndrome

Schnitzler Syndrome, caused by an elevated level of the protein monoclonal IgM gammopathy in the blood, results in a red, hive-like rash and painful, swollen joints.