Post-Campylobacter Guillain Barré Syndrome in the USA: secondary analysis of surveillance data collected during the 2009-2010 novel Influenza A (H1N1) vaccination campaign.

Guillain Barré syndrome (GBS), which is triggered by autoantibodies produced in response to antigenic stimuli such as certain infections and vaccinations, is the most common cause of acute flaccid paralysis worldwide. Campylobacter, the most common bacterial enteric infection in the USA, is reported to be the most commonly diagnosed antecedent of GBS, yet little information is available about the risk of post-Campylobacter GBS. Data collected through active, population-based surveillance in the Emerging Infections Program during the 2009-2010 novel Influenza A (H1N1) vaccination campaign allowed us to compare confirmed and probable GBS cases to non-cases to determine whether antecedent Campylobacter infection (or a diarrhoeal illness consistent with campylobacteriosis) was more common among cases and to assess the risk of GBS following Campylobacter infection. We estimate that 8-12% of GBS cases in the USA are attributable to Campylobacter infection (or a diarrhoeal illness consistent with campylobacteriosis), with 434-650 cases of post-diarrhoeal GBS annually and about 49 cases of GBS per 100 000 Campylobacter infections. These results provide updated estimates for post-Campylobacter GBS incidence in the USA and highlight an important benefit of effective measures to prevent Campylobacter infections.

Subacute sclerosing panencephalitis in the differential diagnosis of encephalitis.

The authors describe five cases of subacute sclerosing panencephalitis (SSPE) identified through the California Encephalitis Project that emphasize the importance of considering SSPE in the differential diagnosis of encephalitis, particularly among pediatric patients. SSPE was not suspected in the differential diagnosis of three of the cases until results of measles testing were known. The diagnosis of SSPE is often not considered by clinicians because of its rarity in the United States and the nonspecific clinical manifestations at onset.

Bioterrorism-related inhalational anthrax: the first 10 cases reported in the United States.

From October 4 to November 2, 2001, the first 10 confirmed cases of inhalational anthrax caused by intentional release of Bacillus anthracis were identified in the United States. Epidemiologic investigation indicated that the outbreak, in the District of Columbia, Florida, New Jersey, and New York, resulted from intentional delivery of B. anthracis spores through mailed letters or packages. We describe the clinical presentation and course of these cases of bioterrorism-related inhalational anthrax. The median age of patients was 56 years (range 43 to 73 years), 70% were male, and except for one, all were known or believed to have processed, handled, or received letters containing B. anthracis spores. The median incubation period from the time of exposure to onset of symptoms, when known (n=6), was 4 days (range 4 to 6 days). Symptoms at initial presentation included fever or chills (n=10), sweats (n=7), fatigue or malaise (n=10), minimal or nonproductive cough (n=9), dyspnea (n=8), and nausea or vomiting (n=9). The median white blood cell count was 9.8 X 10(3)/mm(3) (range 7.5 to 13.3), often with increased neutrophils and band forms. Nine patients had elevated serum transaminase levels, and six were hypoxic. All 10 patients had abnormal chest X-rays; abnormalities included infiltrates (n=7), pleural effusion (n=8), and mediastinal widening (seven patients). Computed tomography of the chest was performed on eight patients, and mediastinal lymphadenopathy was present in seven. With multidrug antibiotic regimens and supportive care, survival of patients (60%) was markedly higher (<15%) than previously reported.

SA-1 antigen expression in small intensely fluorescent cells is associated with proliferation.

Sympathetic neurons, chromaffin cells, and small, intensely fluorescent (SIF) cells are thought to derive from a common sympathoadrenal precursor cell. Sympathoadrenal precursor cells and adrenal chromaffin cells have been shown to react with an antibody, SA-1; we now report that, like sympathoadrenal precursors, SIF cells during their proliferative phase transiently possess this epitope. Precursors and SIF cells were identified in double-label studies of the superior cervical ganglion (SCG) using SA-1 and an antibody that identifies a noradrenergic trait, tyrosine hydroxylase (TH). At E16 when the earliest SIF precursors were detected and at birth, while postmitotic principal neurons had lost SA-1 reactivity, many SIF cells expressed both TH and SA-1. As development proceeded, the proportion of SIF cells expressing only TH increased. In addition, some small SIF-like cells possessed only SA-1 reactivity at birth. Some SIF cells at P7 possessed SA-1, but it was absent at P10 and in the adult. Bromodeoxyuridine (BrdU) was used to identify proliferating SIF cells, and SA-1+ expression was correlated with the period of SIF cell proliferation. At late embryogenesis, the proportion of SA-1+ SIF cells that possessed BrdU was relatively large (17% at E20), and decreased as SIF cell division ceased (6% at P1). Our results indicate that SA-1 is present on SIF cells when these cells are capable of cell division. In addition, mature SIF cells lack SA-1 and are therefore antigenically distinct from the sympathoadrenal precursor. These data suggest that the expression of SA-1 is correlated with the ability of sympathoadrenal cells to proliferate, in the SCG early during embryogenesis, chromaffin cells both during embryogenesis and in the adult, and SIF cells during their transient period of division in the SCG.