Drug reactions
Drug-induced lupus erythematosus is a (generally) reversible condition that usually occurs in people being treated for a long-term illness. Drug-induced lupus mimics SLE. However, symptoms of drug-induced lupus generally disappear once the medication that triggered the episode is stopped. More than 38 medications can cause this condition, the most common of which are procainamide, isoniazid, hydralazine, quinidine, and phenytoin. Non-systemic forms of lupus
Discoid (cutaneous) lupus is limited to skin symptoms and is diagnosed by biopsy of rash on the face, neck, scalp or arms. Approximately 5% of people with DLE progress to SLE. Pathophysiology
SLE is triggered by environmental factors that are unknown. In SLE, the bodys immune system produces antibodies against self-protein, particularly against proteins in the cell nucleus. These antibody attacks are the immediate cause of SLE.SLE is a chronic inflammatory disease believed to be a type III hypersensitivity response with potential type II involvement. Reticulate and stellate acral pigmentation should be considered a possible manifestation of SLE and high titers of anti-cardiolipin antibodies, or a consequence of therapy.People with SLE have intense polyclonal B-cell activation, with a population shift towards immature B cells. Memory B cells with increased CD27+/IgD—are less susceptible to immunosuppression. CD27-/IgD- memory B cells are associated with increased disease activity and renal lupus. T cells, which regulate B-cell responses and infiltrate target tissues, have defects in signaling, adhesion, co-stimulation, gene transcription, and alternative splicing.
Some of these mutations include a 1-base pair duplication in exon 4, a 2-base pair insertion in exon 2, a 1-base pair deletion in exon 4, and a 329-base pair deletion in exon 4 of the gene. The above mutations cause a frameshift in the gene. A frameshift mutation refers to a condition in which the reading frame of the gene is disrupted by the insertion or deletion of base pairs from the gene (if the number of inserted or deleted base pairs is not divisible by three). This frameshift mutation ultimately results in a premature termination codon (the formation of a termination codon at a position more "forward" than normal). Other mutations include a base pair transition in the start codon, which is the starting site of translation of the gene. A transition mutation occurring at this codon disrupts the codon sequence and abolishes the site. This prevents the cell from carrying out translation of the gene. Diagnosis
The diagnosis of Filippi Syndrome is mostly done postnatally. Initial diagnosis of the disease relies on clinical observation of symptoms, including different degrees of syndactyly and craniofacial abnormalities, exhibited by affected individuals. Diagnosis can also be done through radiography, which checks for malformation of digits.Confirmation of diagnosis requires the use of genetic testing.