Diagnosis can be made solely on the basis of history and physical examination in people who present with only facial asymmetry. For those who report neurological symptoms such as migraine or seizures, MRI scan of the brain is the imaging modality of choice. A diagnostic lumbar puncture and serum test for autoantibodies may also be indicated in people who present with a seizure disorder of recent onset.

Because vision loss is often an early sign, Batten disease/NCL may be first suspected during an eye exam. An eye doctor can detect a loss of cells within the eye that occurs in the three childhood forms of Batten disease/NCL. However, because such cell loss occurs in other eye diseases, the disorder cannot be diagnosed by this sign alone. Often an eye specialist or other physician who suspects Batten disease/NCL may refer the child to a neurologist, a doctor who specializes in disease of the brain and nervous system. In order to diagnose Batten disease/NCL, the neurologist needs the patient's medical history and information from various laboratory tests.

Diagnostic tests used for Batten disease/NCLs include:

- Skin or tissue sampling. The doctor can examine a small piece of tissue under an electron microscope. The powerful magnification of the microscope helps the doctor spot typical NCL deposits. These deposits are found in many different tissues, including skin, muscle, conjunctiva, rectal and others. Blood can also be used. These deposits take on characteristic shapes, depending on the variant under which they are said to occur: granular osmophilic deposits (GRODs) are generally characteristic of INCL, while curvilinear profiles, fingerprint profiles, and mixed-type inclusions are typically found in LINCL, JNCL, and ANCL, respectively.

- Electroencephalogram or EEG. An EEG uses special patches placed on the scalp to record electrical currents inside the brain. This helps doctors see telltale patterns in the brain's electrical activity that suggest a patient has seizures.

- Electrical studies of the eyes. These tests, which include visual-evoked responses (VER) and electroretinograms (ERG), can detect various eye problems common in childhood Batten disease/NCLs.

- Brain scans. Imaging can help doctors look for changes in the brain's appearance. The most commonly used imaging technique is computed tomography (CT), which uses x-rays and a computer to create a sophisticated picture of the brain's tissues and structures. A CT scan may reveal brain areas that are decaying in NCL patients. A second imaging technique that is increasingly common is magnetic resonance imaging, or MRI. MRI uses a combination of magnetic fields and radio waves, instead of radiation, to create a picture of the brain.

- Enzyme assay. A recent development in diagnosis of Batten disease/NCL is the use of enzyme assays that look for specific missing lysosomal enzymes for infantile and late infantile only. This is a quick and easy diagnostic test.

In order to qualify a patient's condition as BSS, the bending angle must be greater than 45 degrees. While the presence of the condition is very easy to note, the cause of the condition is much more difficult to discern. Conditions not considered to be BSS include vertebral fractures, previously existing conditions, and ankylosing spondylitis. Lower-back CT scans and MRIs can typically be used to visualize the cause of the disease. Further identification of the cause can be done by histochemical or cellular analysis of muscle biopsy.

Camptocormia is becoming progressively found in patients with Parkinson's disease.

The diagnosis of Parkinson's-associated camptocormia includes the use of imaging of the brain and the spinal cord, along with electromyography or muscle biopsies.

Muscle biopsies are also a useful tool to diagnose camptocormia. Muscle biopsies found to have variable muscle fiber sizes and even endomysial fibrosis may be markers of bent spine syndrome. In addition, disorganized internal architecture and little necrosis or regeneration is a marker of camptocormia.

Patients with camptocormia present with reduced strength and stooped posture when standing due to weakened paraspinous muscles (muscles parallel to the spine). Clinically, limb muscles show fatigue with repetitive movements. Paraspinous muscles undergo fat infiltration. Electromyography may be used as well in diagnosis. On average, the paraspinous muscles of affected individuals were found to be 75% myopathic, while limb muscles were 50% percent myopathic. Creatine kinase activity levels in skeletal muscle are a diagnostic indicator that can be identifiable through blood tests.

Initially, the clinical presentation of SDS may appear similar to cystic fibrosis. However, CF can be excluded with a normal chloride in sweat test but faecal elastase as a marker of pancreatic function will be reduced. The variation, intermittent nature, and potential for long-term improvement of some clinical features make this syndrome difficult to diagnose. SDS may present with either malabsorption, or hematological problems. Rarely, SDS may present with skeletal defects, including severe rib cage abnormalities that lead to difficulty in breathing. Diagnosis is generally based on evidence of exocrine pancreatic dysfunction and neutropenia. Skeletal abnormalities and short stature are characteristics that can be used to support the diagnosis. The gene responsible for the disease has been identified and genetic testing is now available. Though useful in diagnostics, a genetic test does not surmount the need for careful clinical assessment and monitoring of all patients.

An alkaline phosphatase isoenzyme test can be done to check for elevated ALP levels. Tissues that contain high levels of ALP include the liver, bile ducts, and bones. Normal levels of ALP range from (44 to 147) U/L (units per liter) and significantly elevated levels may be an indication of conditions such as various types of cancer, bone disease such as Paget disease, liver disease such as hepatitis, blood disorders, or other conditions.

Elevated alkaline phosphatase is most commonly caused by liver disease or bone disorders. Testing for ALP primarily consists of obtaining a blood sample from a patient along with several other tests for the disorder in question that may be associated with the increase in ALP in the blood serum. It is possible to distinguish between the different forms (isoenzymes) of ALP produced by different types of tissues in the body, in order to pinpoint what's causing the increase of ALP, in order to treat the patient for either liver disease or bone disorder. A more rapid way for testing ALP concentration is by using "p"-nitrophenyl phosphate as substrate. The required volume of serum is 5 mm. for each testing. The sample is first incubated for 30 min. at 38 °C, in a buffered solution in the presence of "p"-nitrophenyl phosphate. By the action of ALP, phosphate groups are removed from the substrate and "para"- nitrophenol is liberated giving off a yellow color in solution which can be measured spectrophotometrically.

Normally, children and adolescents have higher Alkaline Phosphatase levels than adults due to an increase in bone growth. ALP is especially high during a period of growth spurt which occurs are different ages in boys and girls.

The older classification of NCL divided the condition into four types (CLN1, CLN2, CLN3, and CLN4) based upon age of onset, while newer classifications divide it by the associated gene.

CLN4 (unlike CLN1, CLN2, and CLN3) has not been mapped to a specific gene.

Clinical studies have revealed that camptocormia may be hereditary; however, the inheritance mechanism remains unclear. Current areas of research include molecular and genetic studies aimed at elucidating a possible inheritance model along with molecular pathological mechanisms and proteins responsible for BSS. This research will help will facilitate improvement in the classification, diagnosis, and treatment of the condition. In addition, new technologies and animal models of postural abnormalities are being developed to understand camptocormia and design more effective treatment methods.

Because an individual with an enchondroma has few symptoms, diagnosis is sometimes made during a routine physical examination, or if the presence of the tumor leads to a fracture. In addition to a complete medical history and physical examination, diagnostic procedures for enchondroma may include the following:

- x-ray - On plain film, an enchondroma may be found in any bone formed from cartilage. They are lytic lesions that usually contain calcified chondroid matrix (a "rings and arcs" pattern of calcification), except in the phalanges. They may be central, eccentric, expansile or nonexpansile.

Differentiating an enchondroma from a bone infarct on plain film may be difficult. Generally, an enchondroma commonly causes endosteal scalloping while an infarct will not. An infarct usually has a well-defined, sclerotic serpentine border, while an enchondroma will not. When differentiating an enchondroma from a chondrosarcoma, the radiographic image may be equivocal; however, periostitis is not usually seen with an uncomplicated enchondroma.

- radionuclide bone scan - a nuclear imaging method to evaluate any degenerative and/or arthritic changes in the joints; to detect bone diseases and tumors; to determine the cause of bone pain or inflammation. This test is to rule out any infection or fractures.

- magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body. This test is done to rule out any associated abnormalities of the spinal cord and nerves.

- computed tomography scan (Also called a CT or CAT scan.) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than general x-rays.

Medical management may involve immunosuppressive drugs such as methotrexate, corticosteroids, cyclophosphamide, and azathioprine. No randomized controlled trials have yet been conducted to evaluate such treatments, so the benefits have not been clearly established.

Pancreatic exocrine insufficiency may be treated through pancreatic enzyme supplementation, while severe skeletal abnormalities may require surgical intervention. Neutropenia may be treated with granulocyte-colony stimulating factor (GCSF) to boost peripheral neutrophil counts. However, there is ongoing and unresolved concern that this drug could contribute to the development of leukemia. Signs of progressive marrow failure may warrant bone marrow transplantation (BMT). This has been used successfully to treat hematological aspects of disease. However, SDS patients have an elevated occurrence of BMT-related adverse events, including graft-versus-host disease (GVHD) and toxicity relating to the pre-transplant conditioning regimen. In the long run, study of the gene that is mutated in SDS should improve understanding of the molecular basis of disease. This, in turn, may lead to novel therapeutic strategies, including gene therapy and other gene- or protein-based approaches.

Osteochondromas are often asymptomatic and may not cause any kind of discomfort. They are often found accidentally when an X-ray is done for an unrelated reason.

- X-rays are the first tests performed that characterize a lesion. They show a clear picture of dense structures of bones, and will also indicate bone growth pertaining to osteochondroma.

- Computed Tomography (CT) scan can identify the bony lesion in great details and show the presence of calcification. These tests also provide great details, especially in soft tissues with the aide of cross-sectional images.

- Magnetic Resonance Imaging (MRI) is the most accurate method for detecting bone masses in symptomatic cases to depict precise morphology of a tumor. It is used to verify if the palpable mass is continuous with the cortex of the affected bone and to differentiate an osteochondroma from other lesions on the surface of the bone. MRI can also be used to look for cartilage on the surface of tumor and can depict any vascular complications caused by the tumor. An MRI can identify tumors of the spinal column and is often used to diagnose low grade osteosarcoma.

- Ultrasound is done if aneurysms or pseudoaneurysms and venous or arterial thrombosis is suspected. Ultrasound is an accurate method for examining the cartilaginous cap of the osteochondroma. It is also a way of pinpointing bursitis. However, it cannot be used to predict if the growth of tumor is inward in regards to the cap.

- Angiography is used to detect vascular lesions caused by osteochondroma due to ossified cartilaginous cap. It is also used to characterize malignant transformation lesions through neovascularity.

- Clinical testing such as sequence analysis can be done of the entire coding regions of both "EXT1" and "EXT2" to detect mutations.

- A biopsy of the tissue sample of the tumor can also be taken to check for cancer.

Tests for osteochondroma can also identify diseases such as secondary peripheral chondrosarcoma and Multiple osteochondromatosis. In large, secondary chondrosarcoma arises at the site of osteochondroma due to increased thickness of the cartilage cap indicating potential malignant transformation. The symptoms of multiple osteochondromatosis are similar to solitary osteochondroma, but they are often more severe. Painless bumps can arise at the site of tumor and pain and other discomforts can also take place if pressure is put on the soft tissues, nerves, or blood vessels. Dysplasia Epiphysealis Hemimelica (DEH) or Trevor's disease and metachondromatosis (MC) are considered differential diagnosis of both solitary and hereditary osteochondromas. DEH is described as a type of over growth at one or more epiphyses. Similar to osteochondroma, DEH is diagnosed prior to 15 years of age and the growth of lesions end at puberty, when the growth plates close. Metachondromatosis is a rare disorder that exhibit symptoms of both multiple osteochondromas and enchondromas in children and is also inherited in autosomal dominant mode.

Prognosis is poor. Previous research suggested a 100% mortality rate for those with acrania. This disease is rare, occurring in 1 in 20,000 live births.

In order to better manage an acrania diagnosis, early detection is of extreme importance so that actions may be taken to help the mother and child. Families may choose either to terminate the pregnancy, or to carry the child to term. Acrania may cause a fetus to spontaneously abort before reaching term.

The following are the most common treatments of elevated alkaline phosphatase.

- Treatment of the underlying condition

- Once doctors identifies the cause of elevated ALP and diagnose a treatment, the levels of alkaline phosphatase fluctuates back to normal

- Removal of medication - that is associated with increased levels of alkaline phosphatase

- Birth control pills

- Anti-inflammatory medication

- Narcotic medication

- Hormonal drug

- Steroid

- Antidepressant

- Dietary changes

- Include foods rich in vitamin D

- Lifestyle change

- Healthy diet in association with physical exercise

- Exposure to sunlight which increases the production of vitamin D

Feline hepatic lipidosis shares similar symptoms to other problems, including liver disease, renal failure, feline leukemia, Feline infectious peritonitis and some cancers. Diagnosis requires tests that target the liver to make an accurate diagnosis. Jaundice is highly indicative of the disease. Blood tests and a liver biopsy will confirm the presence of the disease.

In addition to genetic tests involving the sequencing of "PEX" genes, biochemical tests have proven highly effective for the diagnosis of Zellweger syndrome and other peroxisomal disorders. Typically, Zellweger syndrome patients show elevated very long chain fatty acids in their blood plasma. Cultured primarily skin fibroblasts obtained from patients show elevated very long chain fatty acids, impaired very long chain fatty acid beta-oxidation, phytanic acid alpha-oxidation, pristanic acid alpha-oxidation, and plasmalogen biosynthesis.

a nuclear imaging method to evaluate any degenerative and/or arthritic changes in the joints; to detect bone diseases and tumors; to determine the cause of bone pain or inflammation. This test is to rule out other cysts (which are quite unusual)

There are three methods of scanning that detect angiomyolipoma: ultrasound, CT and MRI. Ultrasound is standard and is particularly sensitive to the fat in angiomyolipoma but less so to the solid components. However it is hard to make accurate measurements with ultrasound, particularly if the angiomyolipoma is near the surface of the kidney (Maclean Grade III). Computed tomography (CT) is very detailed and fast and allows accurate measurement. However, it exposes the patient to radiation and the dangers that a contrast dye used to aid the scanning may itself harm the kidneys. Magnetic resonance imaging (MRI) is safer than CT but many patients (particularly those with the learning difficulties or behavioural problems found in tuberous sclerosis) require sedation or general anaesthesia and the scan cannot be performed quickly. Some other kidney tumours contain fat, so the presence of fat isn't diagnostic. It can be difficult to distinguish a fat-poor angiomyolipoma from a renal cell carcinoma (RCC). Both minimal fat AMLs and 80% of the clear cell type of RCC display signal drop on an out-of-phase (OOP) MRI sequence compared to in-phase (IP). Thus, a lesion growing at greater than 5 mm per year may warrant a biopsy for diagnosis.

Incidental discovery of angiomyolipomas should trigger consideration of tuberous sclerosis complex (TSC) and lymphangioleiomyomatosis, especially if they are large, bilateral and/or multiple. Screening for TSC includes a detailed physical exam, including dermatologic and ophthalmologic evaluations, by TSC expert clinicians and a CT or MRI of the brain. Screening for LAM includes a high resolution CT of the lung and pulmonary function testing.

Specific treatment for enchondroma is determined by a physician based on the age, overall health, and medical history of the patient. Other considerations include:

- extent of the disease

- tolerance for specific medications, procedures, or therapies

- expectations for the course of the disease

- opinion or preference of the patient

Treatment may include:

- surgery (in some cases, when bone weakening is present or fractures occur)

- bone grafting - a surgical procedure in which healthy bone is transplanted from another part of the patient's body into the affected area.

If there is no sign of bone weakening or growth of the tumor, observation only may be suggested. However, follow-up with repeat x-rays may be necessary. Some types of enchondromas can develop into malignant, or cancerous, bone tumors later. Careful follow-up with a physician may be recommended.

CT scans use x-rays and computer technology to produce accurate axial, coronal, and sagittal images. CT scans are more detailed than x-rays because they can create images that show fat, muscles, organs, and bones.

Acrania can be diagnosed early in pregnancy through an ultrasound. This abnormality appears during the beginning or end of the fourth week of the fetus's development. An absence of the skull is needed in order to make a diagnosis. A presence of brain tissue will confirm the diagnosis of acrania and differentiate it from other developmental problems such as anencephaly.

Most myelolipomas are unexpected findings on CT scans and MRI scans of the abdomen. They may sometimes be seen on a plain X-ray films.

Fine needle aspiration may be performed to obtain cells for microscopic diagnosis.

The malabsorption resulting from lack of bile acid has resulted in elemental formula being suggested, which are low in fat with < 3% of calories derived from long chain triglycerides (LCT). However, reduced very long chain fatty acids (VLCFA) has not been shown to reduce blood VLCFA levels , likely because humans can endogenously produce most VLCFA. Plasma VLCFA levels are decreased when dietary VLCFA is reduced in conjunction with supplementation of Lorenzo’s oil (a 4:1 mixture of glyceryl trioleate and glyceryl trierucate) in X-ALD patients . Since docosahexaenoic acid (DHA) synthesis is impaired [59], DHA supplementation was recommended, but a placebo-controlled study has since showed no clinical efficacy . Due to the defective bile acid synthesis, fat soluble supplements of vitamins, A, D, E, and K are recommended.

Malouf syndrome (also known as "congestive cardiomyopathy-hypergonadotropic hypogonadism syndrome") is a congenital disorder that causes one or more of the following symptoms: mental retardation, ovarian dysgenesis, congestive cardiomyopathy, broad nasal base, blepharoptosis, and bone abnormalities, and occasionally marfanoid habitus (tall stature with long and thin limbs, little subcutaneous fat, arachnodactyly, joint hyperextension, narrow face, small chin, large testes, and hypotonia).

This disease is named after J. Malouf, who performed a case study on a family suffering from this disease in 1985.

Medical diagnosis of CGL can be made after observing the physical symptoms of the disease: lipoatrophy (loss of fat tissues) affecting the trunk, limbs, and face; hepatomegaly; acromegaly; insulin resistance; and high serum levels of triglycerides. Genetic testing can also confirm the disease, as mutations in the AGPAT2 gene is indicative of CGL1, a mutation in the BSCL2 gene is indicative of CGL2, and mutations in the CAV1 and PTRF genes are indicative of CGL3 and CGL4 respectively. Physical diagnosis of CGL is easier, as CGL patients are recognizable from birth, due to their extreme muscular appearance, which is caused by the absence of subcutaneous fat.

CGL3 patients have serum creatine kinase concentrations much higher than normal (2.5 to 10 times the normal limit). This can be used to diagnose type 3 patients and differentiate them from CGL 1 and 2 without mapping their genes. Additionally, CGL3 patients have low muscle tone when compared with other CGL patients.

Macrocephaly is customarily diagnosed if head circumference is greater than two standard deviations (SDs) above the mean. Relative macrocephaly occurs if the measure is less than two SDs above the mean, but is disproportionately above that when ethnicity and stature are considered. In research, cranial height or brain imaging is also used to determine intracranial volume more accurately.