RIN2 deficiency results in macrocephaly, alopecia, cutis laxa, and scoliosis: MACS syndrome.

Inherited disorders of elastic tissue represent a complex and heterogeneous group of diseases, characterized often by sagging skin and occasionally by life-threatening visceral complications. In the present study, we report on an autosomal-recessive disorder that we have termed MACS syndrome (macrocephaly, alopecia, cutis laxa, and scoliosis). The disorder was mapped to chromosome 20p11.21-p11.23, and a homozygous frameshift mutation in RIN2 was found to segregate with the disease phenotype in a large consanguineous kindred. The mutation identified results in decreased expression of RIN2, a ubiquitously expressed protein that interacts with Rab5 and is involved in the regulation of endocytic trafficking. RIN2 deficiency was found to be associated with paucity of dermal microfibrils and deficiency of fibulin-5, which may underlie the abnormal skin phenotype displayed by the patients.

In vitro release of interferon-gamma from peripheral blood lymphocytes in cutaneous adverse drug reactions.

BACKGROUND: Cutaneous drug reactions are common but diagnostically challenging due to phenotypic heterogeneity and simultaneous exposure to multiple drugs. These limitations prompted the development of diagnostic tests. AIMS: To evaluate the performance of an in vitro assay measuring interferon-gamma release from patients' lymphocytes in the presence of causative drugs for the diagnosis of drug reactions. METHODS: Mononuclear cells derived from patients were incubated with and without suspected drugs, and increment of interferon-gamma levels was measured by ELISA. We performed a telephonic survey to evaluate the effect of stopping the drugs incriminated by the assay on cutaneous manifestations. RESULTS: We assessed 272 patients who used 1035 medications. When assessed against the questionnaire data collected at least 6 months after stopping the causative drug, sensitivity was found to be 83.61% and specificity 92.67%. Likelihood ratio for a positive test is 11.40 and for a negative test 0.18. Positive predictive value is 75.37% and negative predictive value is 95.47%. The test was found to perform significantly better in females and in older patients. CONCLUSIONS: Interferon-gamma release test is a useful adjunct tool in the diagnosis of cutaneous drug reactions.

Effects of 5-fluorouracil on human mitogen-activated peripheral blood lymphocytes from healthy individuals.

BACKGROUND: The effect of 5-fluorouracil (5-FU) on activated lymphocytes was explored. MATERIALS AND METHODS: The in vitro effects of 5-FU on DNA synthesis in mitogen-activated lymphocytes from healthy volunteers were compared to those of the antimetabolites doxorubicin, cyclophosphamide and 6-mercaptopurine. These effects were assessed by alterations in the phenotypic profile and the percentage of cells in various phases of the cell cycle, as well as by the secretion of T helper (Th)1 and Th2 cytokines (ELISA). RESULTS: Unlike 5-FU, the other antimetabolites failed to augment DNA synthesis in activated lymphocytes. The effect of 5-FU correlated with an increase in the percentage of cells in the S-phase and caused an increased in CD4+ cells, a decrease in CD56+ cells and a shift of the cytokine secretion pattern from Th2 to Th1. CONCLUSION: 5-FU exhibited a unique effect on DNA synthesis in activated lymphocytes which was accompanied by selective effects on various lymphocyte subpopulations.

In vitro interferon-gamma release test in patients with drug-induced pemphigus.

BACKGROUND: Drug-specific CD8+ TH1 lymphocytes have been found in the peripheral blood and involved skin of patients with drug-induced bullous exanthems. OBJECTIVES: To determine whether the interferon-gamma release test can identify culprit drugs in pemphigus patients. METHODS: Clinical and laboratory workup for pemphigus was performed in 14 pemphigus vulgaris patients who had been exposed to drugs, and the IFN-gamma release test was conducted on their lymphocytes from heparinized venous blood cultured with medium, phytohemagglutinin and one of 32 drugs, or medium and phytohemagglutinin alone. RESULTS: Ten of the patients and 13 of the 32 drugs exhibited a positive response to the test. Eight of the 10 patients with positive IFN-gamma test results had a less severe course of the disease, with fast reduction in steroid dosage. CONCLUSIONS: The findings demonstrate both the ability of the IFN-gamma release test to identify drugs that can induce pemphigus, and its usefulness in the diagnostic workup of pemphigus patients.

Chlorpyrifos exacerbating pemphigus vulgaris: a preliminary report and suggested in vitro immunologic evaluation model.

BACKGROUND: There is accumulating evidence on the role of pesticides in the etiology of pemphigus vulgaris (PV). OBJECTIVE: To determine whether chlorpyrifos, an organophosphate pesticide, is involved in the immunopathology of PV. METHODS: Normal human skin biopsy specimens incubated with progressively diluted chlorpyrifos solutions were used as indirect immunofluorescence substrates for sera from two PV patients previously exposed to the agent and from healthy controls. Involvement of T-cell lymphocytes was assessed by release of interferon-g in the presence of chlorpyrifos. RESULTS: In one PV patient, immunofluorescence was strongly positive for the specimen incubated with the pesticide and weakly positive for the specimen incubated with medium alone. Immunofluorescence was negative in the patient under immunosuppression with prednisolone and in all controls. Both patients tested positive on interferon-g assay; controls tested negative. CONCLUSIONS: Findings suggest an immunopathogenic role of chlorpyrifos in PV. Interferon-g cytokine assay with the pesticide combined with immunofluorescence tests may provide an in vitro diagnostic tool in suspected pesticide-induced/exacerbated pemphigus.

The effect of fish oil supplementation on cytokine production in children.

The ex vivo production of inflammatory cytokines during fish oil supplementation (n-3 polyunsaturated fatty acids, n-3 PUFA) is a matter of considerable controversy. Studies on human subjects have generally reported decreased lymphocyte proliferation and decreased production of IL-2, interferon-gamma, IL-1beta, IL-6 and TNF-alpha, but other studies showed no effect or even increased production. There are no published reports on ex vivo cytokine production in children on long-term, n-3 PUFA supplementation. The current double-blind study explored cytokine production by peripheral blood mononuclear cells (PBMCs), with and without lipopolysaccharide (LPS) stimulation in children on 12 weeks' supplementation with 300 mg/day of n-3 PUFA. Twenty-one children (aged 8-12 years) were randomized to receive 1 g canola oil (control) or 300 mg n-3 PUFA + 700 mg canola oil in a chocolate spread. Blood was then drawn and PBMCs were separated and cultured for 24 h in a culture medium with or without 10 microg/mL LPS for 5 x 10(6) PBMCs. The pro-inflammatory cytokines, IL-1beta, TNF-alpha and IL-6, and the anti-inflammatory cytokines, IL-10 and IL-1RA, were evaluated by ELISA. The levels of all the cytokines were higher in non-stimulated and LPS-stimulated cultures, from n-3 PUFA-treated subjects as compared to controls. There was no difference in the IL-1beta/IL-1RA ratio between the two groups, with and without LPS stimulation. Nevertheless, the ratio tended to be lower in the treated subjects on both occasions. In conclusion, our results indicate an increased production of both pro-inflammatory and anti-inflammatory cytokines, with and without LPS stimulation, in children on 12 weeks' n-3 PUFA supplementation.

Interferon-gamma (INF-gamma) release test can detect cutaneous adverse effects to statins.

BACKGROUND: An increasing number of cutaneous adverse effects are being reported as use of statins becomes more widespread. A study was undertaken to establish the relationship between statin and a cutaneous reaction by the in vitro interferon-gamma (INF-gamma) release test. METHODS: The lymphocytes of 20 patients with suspected drug-induced skin reaction were incubated with and without the drug. The level of INF-gamma from the supernatant was measured by enzyme-linked immunosorbent assay (ELISA), and the increase calculated. RESULTS: Response was positive in 27 (21.43%) of the 126 drugs. Statin was the only drug with a positive response in 80% of those cases. Nine of 20 patients (45.0%) had complete resolution after discontinuation of the drug; 6 (30.0%) who replaced one drug by another statin had partial or no resolution; and 5 (20.0%) had no resolution despite cessation of statins of all kinds. CONCLUSION: A positive INF-gamma release test was found in patients who developed skin reactions while taking statins; the test's reliability was strengthened by prompt improvement following elimination of the suspected drug in the majority of patients.

An unusual case of DRESS syndrome.

BACKGROUND: DRESS syndrome (drug reaction with eosinophilia and systemic symptoms) is a rare but severe drug reaction. OBSERVATIONS: A 27-year-old male with paranoid schizophrenia was hospitalized with all three diagnostic criteria of DRESS syndrome: cutaneous drug eruption, hematological abnormalities (presence of atypical lymphocytes on blood smear) and systemic involvement (generalized lymphadenopathy and hepatitis). On hospitalization the patient exhibited an unusual fever pattern of high temperatures in the morning hours and lower temperatures towards evening. In this case of a patient who needs life-long therapy, we demonstrated the value of the IFN-gamma release test, which showed positive reactivity to 3 out of 9 suspicious drugs: paracetamol, phenytoin and dypirone, allowing for more therapeutic options. After therapy, at 6-month follow-up the patient is doing well under haloperidol treatment, laboratory values including liver function tests are normal and his skin condition is good. CONCLUSION: We suggest that clinicians take the fever pattern of high temperatures in the morning hours and lower temperatures towards evening into account in a patient presenting with a severe cutaneous drug eruption. An interferone-gamma release test may facilitate identification of drugs responsible for the drug reaction.