Congenital fibroblastic connective tissue nevi: Unusual and misleading presentations in three infantile cases.

BACKGROUND: Fibroblastic connective tissue nevi (FCTN) are benign skin conditions characterized by bland spindle cells infiltrating the reticular dermis and the upper subcutis with preservation of adnexal structures. A subset of FCTN expresses CD34, which may cause difficulties in the differential diagnosis, in particular with dermatofibrosarcoma (DFSP). We aim to study clinical and histological main features of congenital FCTN to better understand their heterogeneity. METHODS: We present 3 cases of congenital FCTN with misleading pseudo-tumoral presentations and compare them with published cases in literature. We provide a diagnostic algorithm for congenital neonatal connective tissue tumors. RESULTS: Clinically, FCTN mostly present as well-limited and nontender plaques or nodules mainly located in the neck and face areas or in the trunk. Histologically, FCTN are composed of irregularly distributed fascicles of bland spindled cells and are defined by a list of fundamental features: (i) no atypia, pleomorphism, or mitotic activity; (ii) skin appendages entrapped but unaffected; (iii) no evidence for malignancy. In most cases CD34 is positive, but in some cases, cells can express SMA or are even CD34- and SMA-. CONCLUSION: The initial presentation and natural history of FCTN fit better with a neoplasm than with a hamartoma. Thus, we suggest replacing the term "nevus" with tumor and considering fibroblastic connective tissue tumor (FCTT) as the right denomination of this clinico-pathological entity. FCTTs are difficult to diagnose due to their clinical heterogeneity. Clinical and histological malignant and benign differential diagnoses are discussed.

Monitoring of Cryptosporidium and Giardia river contamination in Paris area.

This study evaluates the protozoan contamination of river waters, which are used for drinking water in Paris and its surrounding area (about 615,000 m(3) per day in total, including 300,000 m(3) for Paris area). Twenty litre samples of Seine and Marne Rivers were collected over 30 months and analyzed for Cryptosporidium oocysts and Giardia cysts detection according to standard national or international methods. Cryptosporidium oocysts and Giardia cysts were found, respectively, in 45.7% and 93.8% of a total of 162 river samples, with occasional high concentration peaks. A significant seasonal pattern was observed, with positive samples for Cryptosporidium more frequent in autumn than spring, summer and winter, and positive samples for Giardia less frequent in summer. Counts of enterococci and rainfalls were significantly associated with Giardia concentration but not Cryptosporidium. Other faecal bacteria were not correlated with monitored protozoan. Marne seems to contribute mainly to the parasitic contamination observed in Seine. Based on seasonal pattern and rainfall correlation, we hypothesize that the origin of contamination is agricultural practices and possible dysfunction of sewage treatment plants during periods of heavy rainfalls. High concentrations of protozoa found at the entry of drinking water plants justify the use of efficient water treatment methods. Treatment performances must be regularly monitored to ensure efficient disinfection according to the French regulations.