Ocular syphilis - a case series of four patients.

Ocular manifestations of syphilis with visual impairment symptoms may occur already at the stage of secondary syphilis. They may also be the only manifestation of syphilis and mimic other diseases of the eye. Therefore, in all patients with uveitis, optic neuritis, optic atrophy, acute ocular muscle paresis, or loss of visual acuity, syphilis infection should be ruled out, even if the medical history does not initially raise suspicion. Ocular involvement should be treated as neurosyphilis. Delayed diagnosis and inadequate therapy are often associated with irreversible consequences for the affected patient. As with any syphilis infection, HIV infection should be considered and excluded, especially in the case of ocular manifestations.

[West-Nile-Virus Infection acquired in Germany in a Kidney Transplant Recipient]. / In Deutschland erworbene West-Nil-Virusinfektion bei einem nierentransplantierten Patienten.

BACKGROUND: West-Nile-Virus (WNV) is a widely distributed flavivirus that is mainly transmitted between birds through different mosquito species (e. g. Culex, Aedes), but may also be transmitted to mammals including humans. WNV causes a spectrum of disease, ranging from asymptomatic infection to encephalitis in a minority of cases. Risk factors for severe disease are older age, cardiovascular disease and an immunocompromised state. MEDICAL HISTORY AND CLINICAL EXAMINATION: Here we report about a 60-year-old male patient who was referred to the University Hospital of Halle (Saale) with severe fever two years after kidney transplantation due to hypertensive nephropathy. No infection focus could be found and by day 6 in the course of his illness the patient developed neurologic symptoms and viral encephalitis was suspected. TREATMENT AND COURSE: The patient was initially treated with aciclovir. After initial reduction of immunosuppression, coincident graft dysfunction was treated with methylprednisolon. WNV-infection was suspected due to recent emerging human cases in the nearby area of the city of Leipzig. WNV lineage 2 was detected in the patient's urine by RT-PCR and seroconversion with presence of anti WNV IgM and IgG could be demonstrated. Consecutively, aciclovir treatment was stopped. The patient fully recovered and the transplanted kidney regained adequate function. Kidney biopsy did not reveal gross rejection of the transplant. CONCLUSION: This case highlights the need to consider rarer causes of illness like WNV-infection particularly in risk groups for more severe outcomes of infectious disease. WNV may be detected by PCR in the blood and cerebrospinal fluid early in the course of infection but it is also excreted for a prolonged period of time in the urine. Seroconversion to anti WNV IgG and IgM may be shown but serologic cross-reactivity among members of the flaviviridae family must be considered.

Livedoid vasculopathy: does hyperhomocysteinaemia play an aetiological role?

BACKGROUND: Livedoid vasculopathy (LV) has been shown to be associated with hypercoagulability. However, relevant genetic and exogenous thrombophilic factors are not fully determined. OBJECTIVES: To evaluate the frequency of hyperhomocysteinaemia (HHCE) and genotypes of hypercoagulative factors in LV patients. MATERIAL AND METHODS: Plasma homocysteine level was measured in 42 LV patients. Polymorphism of MTHFR (677C > T and 1298A > C), PAI1 (-675 5G/4G and -844A > G), and F2 (20210G > A), and the F5 Leiden mutation, as well as biochemical parameters for hypercoagulability, were analysed. RESULTS: Of the LV patients, 62% revealed mild HHCE. Polymorphisms of MTHFR were observed in 75% and 56% and the PAI1 -675 5G/4G polymorphism in 100% and 83% of patients with and without HHCE, respectively. All LV patients with renal failure had mild HHCE. A high level of comorbidity of hypertension (99%) and diabetes type 2 (44%) were noted. CONCLUSION: HHCE seems to play a major pathogenetic role in LV. A high prevalence of further procoagulative factors might support the view that LV is a "complex disease".

[Pitfalls of Differential Diagnosis in Dermatologic Surgery]. / Differenzialdiagnostische Fallstricke aus der Dermatochirurgie.

Evaluation of skin diseases can be challenging for non-dermatologists. Even obvious well-characterized skin pathologies might be misleading and thus treatment can fail. Particularly the differentiation of surgical treated entities is important, for example the management of a wound healing disturbance profoundly differs from that of a pyoderma gangrenosum. This article outlines several easily mistaken pairs of dermatologic entities on one hand and surgical on the other. For example, a livedo vasculopathy can be confused with a leg ulcer, a nail melanoma with a simple hematoma and finally a hidradenitis suppurativa with an axillary abscess. Typical clinical signs and anamnestic data may often lead to the right diagnosis also assisted by the simple fact to "keep it in mind".

Bacillary angiomatosis.

An infection with Bartonella henselae transmitted from domestic cats to humans by scratching normally leads to cat-scratch disease. When the human host has severe immunosuppression or HIV infection, the potentially life-threatening disease bacillary angiomatosis can develop. A 79-year-old man presented with livid-erythematous, angioma-like skin lesions. We considered a cutaneous infiltrate from his known chronic lymphocytic leukemia, Merkel cell carcinoma, cutaneous metastases of internal tumors, cutaneous sarcoidosis, mycobacterial infection and even atypical herpes simplex infection. The correct diagnosis was proven histologically and by PCR. Because of increasing numbers of immunosuppressed and HIV-positive patients, as well as an infection rate of 13% for B. henselae in domestic cats in Germany, one must be alert to the presence of bacillary angiomatosis.

P2Y12 ADP receptor-dependent tyrosine phosphorylation of proteins of 27 and 31 kDa in thrombin-stimulated human platelets.

In thrombin-stimulated human platelets several proteins undergo rapid and transient changes in tyrosine phosphorylation. We demonstrate that a set of proteins of 27, 29, 31, 34, and 39 kDa is affected by released ADP and P2Y12 receptor signaling during platelet activation. AR-C69931MX, an antagonist of the Gi(2)-coupled P2Y12 ADP receptor, inhibits initial tyrosine phosphorylation of p27 and p31 and prevents subsequent dephosphorylation of p29, p34, and p39. Antagonists of the Gq-coupled P2Y1 ADP receptor have no effect. Precluding integrin alpha(IIb)beta(3) outside-in signaling with RGDS or S1197 does not affect the increase in tyrosine phosphorylation of the set of proteins but inhibits their subsequent dephosphorylation. Besides the ADP analogue 2-MeS-ADP, other platelet agonists such as collagen and the TXA(2)-mimetic U46619 also induce p27 and p31 tyrosine phosphorylation in a P2Y12 receptor-dependent manner. Tyrosine phosphorylation of p27 and p31 in response to collagen, but not thrombin, is prevented by aspirin and the TXA(2) receptor antagonist SQ29548, indicating that the effect of collagen strongly relies on TXA(2) signaling. Furthermore, epinephrine, acting via inhibitory Gz-coupled alpha(2A)-adrenoceptors, bypasses the inhibitory effect of AR-C69931MX on thrombin-induced p27 and p31 tyrosine phosphorylation. Finally, we demonstrate that tyrosine phosphorylation of p27 and p31 downstream of P2Y12 receptors is due to the inhibition of adenylyl cyclase but not phosphoinositide 3-kinase (PI 3-K) activation. Elevating cAMP levels with PGI(2) or forskolin precludes thrombin-induced p27 and p31 tyrosine phosphorylation. Moreover, direct inhibition of adenylyl cyclase by SQ22536 reverses the effect of AR-C69931MX. Our data indicate that the observed changes in tyrosine phosphorylation are the result of both primary Gq signaling, initiating the release of ADP, as well as subsequent P2Y12 receptor-mediated Gi coupling.

ADP secretion and subsequent P2Y12 receptor signalling play a crucial role in thrombin-induced ERK2 activation in human platelets.

Stimulating human platelets with thrombin induces the activation of the extracellular signal-regulated kinase 2 (ERK2). We demonstrate that this effect is highly dependent on ADP secretion and P2Y12 receptor signalling. AR-C69931MX (10 microM), a specific antagonist of the Gi-coupled P2Y12 ADP receptor, inhibits ERK2 activation induced by thrombin. Antagonists of the Gq-coupled P2Y1 ADP receptor, A3P5P (500 microM) and MRS2179 (100 microM), have no effect. ADP and its more potent analogue 2-methylthio-ADP alone (both up to 100 microM) do not induce ERK2 activation. Furthermore, we show that the inhibitory effect of AR-C69931MX on ERK2 activation induced by 0.1 U/ml thrombin as well as on platelet aggregation can be bypassed by epinephrine (1 and 10 microM), whereas epinephrine alone has no effect. Epinephrine acts on platelets mainly via alpha(2A)-adrenergic receptors, which, like P2Y12 receptors, couple to inhibitory G proteins. In addition, 2-methylthio-ADP as well as epinephrine provoke ERK2 activation at a thrombin concentration that alone has no detectable effect (0.05 U/ml). Thromboxane A2 (TXA2), which, like ADP, is released by activated platelets, acts as a positive feedback mediator. Stimulating the Gq-coupled TXA2 -receptor with U46619 (10 microM), which leads to ADP secretion and P2Y12 receptor-dependent platelet aggregation, also induces P2Y12-related ERK2 activation. The inhibition of U46619-induced ERK2 activation and platelet aggregation by AR-C69931MX are also rescued by epinephrine. Pretreatment with aspirin inhibits ERK2 activation induced by 0.1 U/ml thrombin, but has no effect at high concentrations of thrombin. The combination of U46619 and thrombin, at concentrations which alone have no effect, provokes ERK2 activation, suggesting that thrombin and released TXA2 act synergistically. Our data indicate that both primary signalling through Gq, which evokes ADP secretion, as well as subsequent coupling via Gi by the P2Y12 receptor are required for ERK2 activation.