Other genetic associations
A fourth gene associated with this condition is the proline-rich transmembrane protein 2 (PRRT2 gene) - an axonal protein associated with the exocytosis complex.A fifth gene associated with this condition is SLC4A4, which encodes the electrogenic NaHCO3 cotransporter NBCe1. Diagnosis
Diagnosis of FHM is made according to these criteria:
Two attacks of each of:Aura with motor weakness accompanied by either reversible visual symptoms (flickering lights, spots, lines, etc. ), reversible sensory symptoms (pins and needles, numbness, etc.) or speech symptoms
At least two occurrences of:One or more aura symptoms that develop over at least 5 minutes
These symptoms lasting more than 5 minutes and less than 24 hours
Headache beginning within 60 minutes of aura onset: These headaches can last 4–72 hours, occur on only one side of the head, pulsate, be of moderate to severe intensity, and may be aggravated by common physical activities such as walking. These headaches must also be accompanied by nausea/vomiting, phonophobia (avoidance of sound due to hypersensitivity), and/or photophobia (avoidance of light due to hypersensitivity).At least one close (first- or second-degree) relative with FHM
No other likely causeSporadic forms follow the same diagnostic criteria, with the exception of family history. In all cases, family and patient histories are used for diagnosis. Brain-imaging techniques, such as MRI, CAT scan, and SPECT, are used to look for signs of other familial conditions such as CADASIL or mitochondrial disease, and for evidence of cerebellar degeneration. With the discovery of causative genes, genetic sequencing can also be used to verify diagnosis (though not all genetic loci are known).
In the clinical laboratory, routine cultures may be held for insufficient time to grow nocardiae, and referral to a reference laboratory may be needed for species identification. Pulmonary infiltration and pleural effusion are usually detected via x-ray. Treatment
Nocardiosis requires at least 6 months of treatment, preferably with trimethoprim/sulfamethoxazole or high doses of sulfonamides. In patients who do not respond to sulfonamide treatment, other drugs, such as ampicillin, erythromycin, or minocycline, may be added.Treatment also includes surgical drainage of abscesses and excision of necrotic tissue. The acute phase requires complete bed rest; as the patient improves, activity can increase.A new combination drug therapy (sulfonamide, ceftriaxone, and amikacin) has also shown promise. Prognosis
The prognosis of nocardiosis is highly variable. The state of the hosts health, site, duration, and severity of the infection all play parts in determining the prognosis. Currently, skin and soft tissue infections have a 100% cure rate, and pleuropulmonary infections have a 90% cure rate with appropriate therapy. The cure rate falls to 63% with those infected with disseminated nocardiosis, with only half of patients surviving infections that cause brain abscess. Additionally, 44% of people who are infected in the central nervous system (CNS) die, increasing to 85% if that person has an already weakened immune system. There are no preventative treatments for nocardiosis. The only recommendation is to protect open wounds to limit entrance of the bacterium. Epidemiology
Although there are no international data available on worldwide infection rates per year, there are roughly 500–1000 documented cases of nocardiosis per year in the US.