Gatifloxacin (brand names Gatiflo, Tequin, and Zymar) is an antibiotic of the fourth-generation fluoroquinolone family, that like other members of that family, inhibits the bacterial enzymes DNA gyrase and topoisomerase IV. It was patented in 1986 and approved for medical use in 1999. Side effects
A Canadian study published in the New England Journal of Medicine in March 2006, claimed that Tequin  can have significant side effects including dysglycemia. An editorial by
Jerry Gurwitz in the same issue called for the Food and Drug Administration (FDA) to consider giving Tequin a black box warning. This editorial followed distribution of a letter dated February 15 by Bristol-Myers Squibb to health care providers indicating action taken with the FDA to strengthen warnings for the medication. Subsequently, Bristol-Myers Squibb reported it would stop manufacture of Tequin, end sales of the drug after existing stockpiles were exhausted, and return all rights to Kyorin.By contrast, ophthalmic gatifloxacin is generally well tolerated. The observed systemic concentration of the drug following oral administration of 400 mg (0.01 ounces) gatifloxacin  is approximately 800 times higher than that of the 0.5% gatifloxacin eye drop. Given as an eye drop, gatifloxacin has very low systemic exposure. Therefore, the systemic exposures resulting from the gatifloxacin ophthalmic solution are not likely to pose any risk for systemic toxicities.
Malignant infantile osteopetrosis is a rare osteosclerosing type of skeletal dysplasia that typically presents in infancy and is characterized by a unique radiographic appearance of generalized hyperostosis (excessive growth of bone). The generalized increase in bone density has a special predilection to involve the medullary portion with relative sparing of the cortices. Obliteration of bone marrow spaces and subsequent depression of the cellular function can result in serious hematologic complications. Optic atrophy and cranial nerve damage secondary to bony expansion can result in marked morbidity. The prognosis is extremely poor in untreated cases. Plain radiography provides the key information to the diagnosis. Clinical and radiologic correlations are also fundamental to the diagnostic process, with additional gene testing being confirmatory. Presentation
Hematologic manifestations related to bone marrow suppression and subsequent pancytopenia are a major source of morbidity and mortality. Additionally, extramedullary hematopoiesis can result in liver and spleen dysfunction. Cranial nerve dysfunction and neurologic complications are usually associated with infantile osteopetrosis. Expansion of the skull bone leads to macrocephaly. Additionally, linear growth retardation that is not apparent at birth, delayed motor milestones and poor dentition can occur. Diagnosis
Skeletal radiography
The generalized increase in bone density of the medullary portion predominates with relative sparing of the cortices. The axial and appendicular skeleton are uniformly involved.