Symptoms and signs out of proportion to what is expected of a particular trauma or sudden worsening of symptoms should alert one of traumatic endophthalmitis [1]. Usually the initial symptoms are masked/modified by the damage induced by primary pathology causing a delay in the diagnosis and poor outcome. Sudden appearance of hypopyon (Fig. 9.2), increasing pain, retinitis, periphlebitis, vitreous haze, and vitreous echoes should alert one of endophthalmitis following trauma [1, 20].

Sometimes the symptoms can be delayed, and there is a mention of endophthalmitis diagnosed as long as 4–60 years following trauma [21]. The hypodermic needle-related injuries in children are particularly notorious for late/delayed presentation. Because of mild transient symptom at time of momentary pinpoint penetration by sharp needle tip, the initial impact is usually ignored by the child and presented few days to week later with severe symptoms. The site of penetration tends to be small and often occult and likely to be overlooked by the attending physician unless searched carefully under slit-lamp high magnification [12]. Bacillus cereus causes the most virulent and refractory form of endophthalmitis [22]. It is characterized by a rapid onset of severe pain and inflammation, hypopyon, chemosis, ring-shaped corneal infiltrate, progression to panophthalmitis, and irreversible destruction of the eye within hours to days. Reports mention a delay in treatment of over 6 h significantly reduces the potential for salvaging useful vision [15] because of permanent damage caused by tissue destructive exoenzymes [2, 22, 23]. Delayed onset, slowly progressive inflammation with minimal discomfort, and fluff or snow balls/string of pearl white inflammatory mass in the vitreous suggest fungal infection [24–26]. However, some of them can have pain and diffuse inflammation like bacterial endophthalmitis [17]; thus, it is prudent to investigate for fungus in addition to bacterial agents even with acute presentation.

Often the media haze does not allow a detailed fundus evaluation and require a gentle B-scan (Fig. 9.3) under aseptic precautions to assess posterior segment. In case and whenever the globe integrity is severely affected, B-scan can be done in the postoperative period as soon as possible after primary repair.

There is no general guideline for management of traumatic endophthalmitis unlike the Endophthalmitis Vitrectomy Study (EVS) recommendation for post-cataract surgery endophthalmitis. Prompt meticulous globe repair with systemic and broad-spectrum intravitreal antibiotics [27, 28] can go a long way in preventing endophthalmitis following acute penetrating injuries [8]. Injuries by needle, retained IOFB, lens rupture, smaller wound length, cases with exclusive corneal laceration, and deep injuries are associated with high risk of endophthalmitis and should urge for high vigilance [13]. Ability to filter out the clinical clues of infection among a variety of vague symptoms and signs of trauma play a crucial role in early detection of traumatic endophthalmitis.

Clinically suspected cases of traumatic endophthalmitis should undergo vitreous biopsy and vitrectomy along with empirical broad-spectrum systemic and intravitreal antibiotics (guided by the trauma history), sometimes in conjunction with the treatment for the primary intraocular trauma. Reports from South India show that vancomycin remains the drug of choice for empiric coverage of gram-positive organisms including Bacillus species, while ceftazidime is still the preferred choice for gram-negative organisms [29]. All cases of clinically diagnosed traumatic endophthalmitis might not have a positive culture in microbiology (culture independent). Similarly, the presence of a positive intraocular culture is not synonymous with endophthalmitis following penetrating trauma [1] and should be judged in the clinical context. Vitrectomy is often indicated for posttraumatic endophthalmitis with a goal to collect samples for microbiology; debulk vitreous toxins, microorganisms, and inflammatory debris; create space for the antibiotics to accumulate and spread; improve media clarity; and repair any underlying retinal pathology including foreign body removal whenever required. As the inflamed retina could be fragile and is prone to tears, one should aim at safe vitrectomy. This can vary depending on the surgeon’s expertise, available set up, and surgical feasibility with respect to coexisting collateral damage. Subsequent management depends upon the culture sensitivity report, clinical response, and complications if any. There is always a scope for an early second surgery once the infection is under control with a superior safety margin.

Endophthalmitis in the setting of a soil-contaminated foreign body has a higher likelihood of infection with Bacillus, Clostridium, and/or fungus and necessitates its prompt removal, if feasible. On the other hand, a metallic projectile penetrating the eye at a very high speed in a clean surrounding could be removed at ease if this cannot be removed safely during primary repair. A ruptured lens should preferably be removed during the primary procedure to avoid inflammation secondary to ruptured lens particles. Intravitreal and systemic steroid act as important adjunct to the primary treatment, take care of the inflammation, hasten recovery, and reduce collateral damage once the microorganisms start responding. However, they have to be used with extreme caution in cases of undetected/untreated fungal infection.

Like any other endophthalmitis, microbiology plays an important role in guiding subsequent treatment after initial management with broad-spectrum antibiotics. Unpredictable, atypical, and rare organisms are more common following penetrating trauma than that related to cataract surgery. One should be vigilant enough to look for additional organisms that might show up in culture plates after initial microbiology report. While a positive culture does not always mean endophthalmitis, a negative culture does not rule it out. Ariyasu et al. found that 33% of open-globe injuries were culture positive when aqueous was sampled. However, none of the patients progressed to develop endophthalmitis [30]. The prevalence of culture-negative cases of posttraumatic endophthalmitis has been reported to range from 17% to 42% [8]. Approximately 75% of all posttraumatic culture-positive endophthalmitis cases are caused by gram-positive organisms with Bacillus causing 20% of the infections [11]. Gram-positive bacilli in initial smear should be taken seriously and treated in the line of Bacillus spp. unless proven otherwise.

Visual prognosis is affected by the virulence of the microbe, attendant inflammation, type of trauma, type and the extent of collateral ocular damage (e.g., retinal break or detachment), presence or absence of IOFB, timing and adequacy of the treatment, and finally immune status of the patient. Posttraumatic endophthalmitis is typically associated with worse visual acuity outcomes compared with postoperative endophthalmitis [31] due to a variety of factors including associated comorbidities, more virulent organisms (Bacillus cereus) [32], and possible delayed diagnosis and initiation of treatment. Because of notoriously rapid progression, the interval between the onset of symptoms and initiation of treatment plays a crucial role in Bacillus endophthalmitis. A comprehensive review of posttraumatic cases of endophthalmitis caused by B. cereus reported that less than 30% of patients regained useful vision and that only 9% regained 20/70 vision or better [4]. Despite therapeutic and surgical intervention, 48% of B. cereus and other Bacillus species infections required evisceration or enucleation of the eye [4]. So early aggressive treatment is crucial for a better outcome [33].