In a single case report
, abatacept produced both clinical improvement and normalization of laboratory parameters in a patient who had failed to respond to methotrexate, TNF inhibitors, steroid, immunoabsorption, plasmapheresis, and IL- inhibition.
The furor was provoked by The New England Journal of Medicine's publication of a single case report
(involving just one incident) and a non-peer-reviewed letter to the editor (which also purported to describe a single incident).
7,8) Interestingly, a recent single case report
by Chim et al (9) describes a clonal T-cell receptor gamma gene rearrangement by polymerase chain reaction in an elderly man with Kimura disease.
Such a variant has been detected in Vietnam also (6), but no information is available on its presence and distribution in other European countries, except for a single case report
from Spain (14).
However, rather than suggesting that a single case report
"contradicts" the anterior horn cell hypothesis, we suggest that WNV-associated flaccid paralysis be viewed as having a spectrum of causes, one of which certainly is poliomyelitis like illness.
The role of p53 gene mutation is unclear but has been observed in more than 80% of SRCC cases, including a single case report
of SRCC in association with papillary carcinoma, which was believed to be of clear cell origin.
3-5] In addition, there is a single case report
in the veterinary literature of a spontaneously occurring, metastasizing, malignant craniopharyngioma in an albino rat, an event as uncommon in animals as it is in humans.
Most of the literature characterizing vulvar smooth muscle tumors comprises single case reports
with reviews of the literature, and few large case series exist.
The majority of publications on MAT in children are single case reports
or small case series.
Encephaloceles of the lateral sphenoid sinus are uncommon, having been described in the literature only in single case reports
and small series.
Congenital malformation incidence rates (for comparison with the rates of malformations in the general population) cannot be determined based on single case reports
of adverse events because there is no denominator (that is, no information on the number of exposed population).
Least valuable will be single case reports
and the claims of manufacturers.