Israel Medical Association Journal

Background: Solar urticaria (SU) is a rare and disabling photodermatosis. SU typically manifests as urticarial wheals and erythema appearing shortly after sun exposure. SU is often initially diagnosed clinically with subsequent confirmation through photoprovocation tests. Early diagnosis is important for correct management of patients.

Objective: To present the clinical features of three cases of atypical presentation of SU and to discuss possible underlying mechanisms.

Methods: We report a series of three patients who presented with transient pruritic erythema without wheals after sun exposure. All patients had photoprovocation tests conducted to confirm SU diagnosis and to determine their action spectra. Treatment outcomes were recorded.

Results: All three patients developed classical manifestations of SU during photoprovocation tests within the UVA1 spectrum. Two patients required high-dose irradiation to provoke urticaria.

Conclusions: Erythema without urticaria can be the primary manifestation of SU, especially in countries with sunny climates where natural skin hardening is common. Such cases require a high index of suspicion for SU and highlight the importance of photoprovocation testing to confirm the diagnosis.

Background: Evaluation of mismatch repair (MMR) deficiency is conducted via immunohistochemistry or by microsatellite instability (MSI) analysis. Heterogeneous immunohistochemistry staining for MMR proteins may show different patterns; however, according to current guidelines, all of those patterns should be interpreted as MMR proficient. This conclusion might lead to false negative results because although most cases of heterogeneity stem from technical factors and biological variability, other types of heterogeneity represent true MMR deficiency.

Objectives: To identify a unique heterogeneity pattern that is associated with true MMR loss.

Methods: We analyzed 145 cases of colorectal carcinoma. Immunohistochemistry staining for MLH1, PMS2, MSH2, and MSH6 were performed. We defined geographic heterogeneity as areas of tumor nuclear staining adjacent to areas of loss of tumor nuclear staining with intact staining in the surrounding stroma. All cases were evaluated for the presence of geographic heterogeneity. In addition, 24 cases were also evaluated by MSI testing.

Results: Of the 145 cases, 24 (16.5%) were MMR deficient. Of the 24 cases for which MSI analysis was also available, 10 cases (41.7%) demonstrated biological heterogeneity, 5 (20.8%) demonstrated technical heterogeneity, and 2 (8.3%) demonstrated geographic heterogeneity. Only the two cases with geographic heterogeneity were MSI-high via MSI analysis. In addition, a germline mutation in MSH-6 was identified in one of these cases.

Conclusions: Geographic heterogeneity may raise a suspicion for a MMR-deficient case, which should be further analyzed using additional methodologies such as MSI analysis.

Background: Patients with multiple (< 100) colorectal adenomatous polyps are at increased risk for colorectal cancer. Genetic evaluation of those patients who test negative for APC gene mutation is both a clinical and economic burden but is critical for counseling and surveillance. In Israel, this is confounded by the fact that national health insurance does not fully cover genetic evaluation of APC gene exon 16.

Objectives: To perform a comprehensive genetic evaluation of APC gene mutation-negative polyposis patients with the aim of developing a future evaluation protocol.

Methods: Genetic analyses were performed in 29 APC gene mutation-negative Jewish individuals with 5 to ≥ 40 colonic adenomas who did not fulfill Amsterdam (clinical) criteria for Lynch syndrome. Analyses included completion of APC gene exon 16 sequencing, analysis for APC gene copy number variations (deletions or duplications), MUTYH gene sequencing, and microsatellite instability in CRC[1] patients fulfilling “Bethesda” (laboratory investigation) criteria for Lynch syndrome.

Results: Completion of APC gene exon 16 sequencing revealed one patient with the E1317Q polymorphism. All were normal by APC multiplex ligation-dependent probe amplification analysis. Pathogenic MUTYH mutations were found in three patients, all of North African origin; two additional patients had variants of unknown significance. One of six patients with Bethesda-positive criteria was MSI²-High with immunohistology consistent with MLH1 mutation.

Conclusions: Based on this small but well-characterized cohort with multiple colorectal adenomas, Lynch syndrome needs to be excluded if there are compatible criteria; otherwise MUTYH sequencing is probably the first step in evaluating APC-negative patients, especially for Jews of North African descent. Completing APC exon 16 sequencing and copy number variations analysis should probably be the last evaluations.

Background: In the course of occurrence of cerebral infarction, cerebral hemorrhage and subarachnoidal hemorrhage episodes, periodicities resembling those found in the solar and geomagnetic activity were found by Kováč and Mikulecký (2005).

Objectives: To investigate putative relationships between two indices of solar activity and one index of geomagnetic activity on one side and the occurrence of cerebral infarction on the other.

Methods: In addition to the 192 monthly cases out of 6100 new cases of cerebral infarction that occurred between January 1989 and December 2004, monthly averages for Wolf numbers, solar flares index and Ap index were included in the analysis. The cross-correlation between each cosmo-geophysical variable on the one hand and the number of new cases of the disease on the other was computed. The quadratic regression with the chosen time delay was also studied using, separately, the Wolf numbers, solar flares and Ap index as the explanatory variable and the number of cases of cerebral infarction as the responding variable.

Results: Significantly negative correlation coefficients between the monthly means of the Wolf numbers, of solar flares and of Ap index on the one hand and monthly numbers of new cases of the disease on the other were found for the delays between -6 and +17 months. The cross-regression results for the delay of +5 months (infarction delayed after each cosmo-geophysical variable by 5 months) displayed a linear decrease except for the Wolf numbers where the parabolic decrease of cases was significant.

Conclusions: An increased intensity of the studied cosmo-geophysical parameters appears to be significantly connected with decreased occurrence of cerebral infarctions, and vice versa. This effect seems to last up to 17 months. The results are supported by a few similar findings in the literature. Putative cosmo-biomedical connections warrant further study to verify them in larger samples and longer time scales. If confirmed, their mechanisms should be elucidated.
 

Background: An increased risk of developing cancer of the skin is the only potentially serious (albeit unproven) long-term side effect of heliotherapy and it is therefore prudent to avoid unnecessary exposure to solar ultraviolet radiation. Traditional heliotherapy for psoriasis at the Dead Sea calls for a sun exposure of 5–6 hours daily for 28 days. Studies have determined that mid-summer exposure for 3 hours is equally effective.

Objectives: To determine the effect of 3 hours sun exposure daily in the heliotherapy of psoriasis at the Dead Sea during the months March to December; and to monitor the associated ambient doses of solar UVB[1] radiation.

Methods: A total of 194 patients with moderate to severe psoriasis was treated in the months of March-December by 3 hours of sun exposure each day. The dose of ambient solar UVB was monitored by a Solar Model 501A UVB-Biometer.

Results: Three hours of sun exposure daily was therapeutically efficacious in all months from March to November, but not in December. The lowest effective cumulative UVB dose was 170 standard erythema dose, recorded in March and November.

Conclusions: Daily sun exposure for the heliotherapy of psoriasis at the Dead Sea can be reduced to at least 3 hours daily, about half the time originally recommended.