Ghons complex is a lesion seen in the lung that is caused by tuberculosis. The lesions consist of a Ghon focus along with pulmonary lymphadenopathy within a nearby pulmonary lymph node. A Ghons complex retains viable bacteria, making them sources of long-term infection, which may reactivate and trigger secondary tuberculosis later in life.In countries where cow milk infected with Mycobacterium bovis has been eliminated (due to culling of infected cows and pasteurization), primary tuberculosis is usually caused by Mycobacterium tuberculosis and almost always begins in the lungs. Typically, the inhaled bacilli implant in the distal airspaces of the lower part of the upper lobe or the upper part of the lower lobe, usually close to the pleura. As sensitization develops, a 1 to 1.5 cm area of gray-white inflammation with consolidation emerges, known as the Ghon focus. In most cases, the center of this focus undergoes caseous necrosis. Tubercle bacilli, either free or within phagocytes, drain to the regional nodes, which also often caseate. This combination of parenchymal lung lesion and nodal involvement is referred to as the Ghon complex. During the first few weeks, there is also lymphatic and hematogenous dissemination to other parts of the body.In approximately 95% of cases, development of cell-mediated immunity controls the infection. Differentiation
The Ghon complex undergoes progressive fibrosis, often followed by radiologically detectable calcification (Ranke complex), and despite seeding of other organs, no lesions develop. Although they are often confused, Ranke complex and Ghon complex are not synonymous.
Delayed pressure urticaria is known as one of the more painful subsets of physical urticaria due to formed hives being deep-seated and appearing after 4–6 hours. Causes
Due to the delayed appearance of wheals, plausible causes are hard to establish; the natural course and/or clinical pattern is variable and inconclusive. Treatment
It was noted that although antihistamines and anti-inflammatory drugs such as, colchicine, sulphasalazine, dapsone, and topical steroid are advocated for in the treatment of DPU, most if not all are unsatisfactory in relieving symptoms. Even a second generation antihistamine, ketotifen, was unable to efficiently and satisfactorily relieve symptoms of DPU


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