​Symptoms and Signs – Differential Diagnosis of Ovarian Mass
• Uterine fibroid
• Tubo-ovarian abscess
• Retroperitoneal cyst/neoplasm
• Pelvic kidney
• Paraovarian cyst
• Ovarian torsion
• Non-neoplastic tumors of ovary: germinal inclusion cyst, follicle cyst, corpus luteum cyst, pregnancy luteoma, theca lutein cysts, sclerocystic ovaries, endometrioma
• Malignant neoplasm: ovary, fallopian tube, colon
• Ectopic pregnancy
• Diverticular abscess/diverticulitis
• Distended bladder
• Appendiceal abscess/appendicitis (especially in children)

​Symptoms and Signs – Differential Diagnosis of Ovulatory Dysfunction
HYPERANDROGENIC ANOVULATION
• Polycystic ovary syndrome
• Late-onset congenital adrenal hyperplasias
• Ovarian hyperthecosis
• Androgen-producing ovarian tumors
• Androgen-producing adrenal tumors
• Cushing’s syndrome
HYPOESTROGENIC ANOVULATION (HYPOTHALAMIC OR
PITUITARY ETIOLOGY)
Hypogonadotropic Hypoestrogenic States
• Reversible
• Functional hypothalamic amenorrhea: eating disorders (anorexia nervosa, excessive weight loss), excessive athletic training
• Neoplastic: craniopharyngioma, pituitary stalk compression
• Infiltrative diseases: histiocytosis X, sarcoidosis
• Hypophysitis
• Pituitary adenomas: hyperprolactinemia, euprolactinemic galactorrhea
• Endocrinopathies: hypothyroidism/hyperthyroidism, Cushing’s disease
• Irreversible
• Kallmann’s syndrome
• Isolated gonadotropin deficiency (hypothalamic or pituitary origin)
• Panhypopituitarism/pituitary insufficiency: Sheehan’s syndrome, pituitary apoplexy, pituitary irradiation or ablation
Hypergonadotropic Hypoestrogenic States
• Physiologic states: menopause, perimenopause
• Premature ovarian failure
• Immune related: radiation therapy/chemotherapy induced
• Ovarian dysgenesis
• Turner’s syndrome
• 46XX with mutations of X
• Androgen insensitivity syndrome
MISCELLANEOUS
• Endometriosis
• Luteal phase defect
* Spontaneous, multivector, chaotic eye movement.

​Symptoms and Signs – Differential Diagnosis of Paget’s Disease of Bone
• Vertebral hemangioma
• Skeletal neoplasm (primary or metastatic)
• Osteomyelitis
• Hyperparathyroidism
• Fibrous dysplasia

Symptoms and Signs – Differential Diagnosis of Paget’s Disease of Breast
• Seborrheic dermatitis
• Melanoma
• Lichen simplex
• Intertrigo
• Florid papillomatosis of the nipple or nipple adenoma
• Eczema
• Contact dermatitis
• Bowen’s disease
• Basal cell carcinoma

​Symptoms and Signs – Differential Diagnosis of Midfoot Pain 
MEDIAL ASPECT
• Tendinitis of posterior tibialis
• Tendinitis of flexor digitorum longus
• Tendinitis of flexor hallucis longus
• Infection (osteomyelitis, septic arthritis, cellulitis) of foot
• Peripheral vascular insufficiency
• Fracture
• Osteoarthritis
• Gout, pseudogout
• Neuropathy
• Tumor
LATERAL ASPECT
• Peroneus longus tendinitis
• Peroneus brevis tendinitis
• Infection (osteomyelitis, septic arthritis, cellulitis) of foot
• Peripheral vascular insufficiency
• Fracture
• Osteoarthritis
• Gout, pseudogout
• Neuropathy
• Tumor

​Symptoms and Signs – Differential Diagnosis of Heel Pain, Plantar Aspect, 
• Tumor
• Tarsal tunnel syndrome
• Plantar fasciitis
• Plantar fascia rupture
• Peripheral vascular insufficiency
• Osteoarthritis
• Neuropathy
• Neuroma
• Infection (osteomyelitis, septic arthritis, cellulitis) of foot
• Heel pad atrophy
• Gout, pseudogout
• Fracture
• Bone cyst

​Symptoms and Signs – Differential Diagnosis of Posterior Heel Pain 
• Tumor
• Retrocalcaneal bursitis
• Retroachilles bursitis
• Peripheral vascular insufficiency
• Osteoarthritis
• Neuropathy
• Infection (osteomyelitis, septic arthritis, cellulitis) of foot
• Gout, pseudogout
• Fracture
• Achilles tendinitis

​Symptoms and Signs – Differential Diagnosis of Palindromic Rheumatism
• Whipple’s disease
• Sarcoidosis
• Reactive arthritis (rare)
• Palindromic rheumatoid arthritis
• Lyme borreliosis, stages 2 and 3
• Essential palindromic rheumatism
• Crystal synovitis (gout, calcium pyrophosphate dihydrate [CPPD], pseudogout, calcific periarthritis) 
• Acute rheumatic fever

​Symptoms and Signs – Differential Diagnosis of Palmoplantar Hyperkeratosis
• Superficial skin infection
• Repeated trauma
• Reiter’s syndrome
• Psoriasis
• Paraneoplastic acrokeratosis
• Chronic eczema

​Symptoms and Signs – Differential Diagnosis of Palpitations
• Wolff-Parkinson-White (WPW) syndrome
• Sick sinus syndrome
• Mitral valve prolapse
• Medications (digoxin, β-blockers, calcium channel antagonists, hydralazines, diuretics, minoxidil)
• Ischemic heart disease
• Ingestion of stimulant drugs (cocaine, amphetamines, caffeine)
• Hypoglycemia in type 1 diabetes mellitus (DM)
• Hyperthyroidism
• Exercise
• Electrolyte abnormalities (hypokalemia, hypomagnesemia)
• Anxiety